<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Erdafitinib and can you explain it in depth? [/INST] Erdafitinib, sold under the brand name Balversa, is an anti-cancer medication. It is a small molecule inhibitor of fibroblast growth factor receptor (FGFR) used for the treatment of cancer. FGFRs are a subset of tyrosine kinases which are unregulated in some tumors and influence tumor cell differentiation, proliferation, angiogenesis, and cell survival. Astex Pharmaceuticals discovered the drug and licensed it to Janssen Pharmaceuticals for further development.Researchers have investigated erdafitinib for safety and efficacy in treatment of bile duct cancer, gastric cancer, non-small cell lung cancer, and esophageal cancer.In March 2018, erdafitinib was granted breakthrough therapy designation by the U.S. Food and Drug Administration (FDA) for treatment of urothelial cancer.In April 2019, erdafitinib was granted approval by the FDA for treatment of metastatic or locally advanced bladder cancer with an FGFR3 or FGFR2 alteration that has progressed beyond traditional platinum-based therapies, subject to a confirmatory trial. The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication.

Side effects
Common side effects include increased phosphate level, mouth sores, feeling tired, change in kidney function, diarrhea, dry mouth, nails separating from the bed or poor formation of the nail, change in liver function, low salt (sodium) levels, decreased appetite, change in sense of taste, low red blood cells (anemia), dry skin, dry eyes and hair loss. Other side effects include redness, swelling, peeling or tenderness on the hands or feet (hand foot syndrome), constipation, stomach pain, nausea and muscle pain.Erdafitinib may cause serious eye problems, including inflamed eyes, inflamed cornea (front part of the eye) and disorders of the retina, an internal part of the eye </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Defibrotide and can you explain it in depth? [/INST] Defibrotide, sold under the brandname Defitelio, is a mixture of single-stranded oligonucleotides that is purified from the intestinal mucosa of pigs. It is used to treat veno-occlusive disease of the liver of people having had a bone marrow transplant, with different limitations in the US and the European Union. It works by protecting the cells lining blood vessels in the liver and preventing blood clotting; the way it does this is not well understood.The most common side effects include abnormally low blood pressure (hypotension), diarrhea, vomiting, nausea and nosebleeds (epistaxis). Serious potential side effects that were identified include bleeding (hemorrhage) and allergic reactions. Defibrotide should not be used in people who are having bleeding complications or who are taking blood thinners or other medicines that reduce the bodys ability to form clots. Use of the drug is generally limited by a strong risk of life-threatening bleeding in the brain, eyes, lungs, gastrointestinal tract, urinary tract, and nose.  Some people have hypersensitivity reactions.Defibrotide was approved for medical use in the European Union in October 2013, in the United States in March 2016, and in Australia in July 2020. Defibrotide is the first FDA-approved therapy for treatment of severe hepatic VOD, a rare and life-threatening liver condition.

Medical uses
In the European Union defibrotide is indicated for the treatment of severe hepatic veno-occlusive disease (VOD) also known as sinusoidal obstructive syndrome (SOS) in hematopoietic stem-cell transplantation (HSCT) therapy for adults, adolescents, children, and infants over one month of age.Defibrotide is used to treat veno-occlusive disease of the liver of people having had a bone marrow transplant, with different limitations in the US and the European Union. As of 2016, however, randomized placebo controlled trials have not been done.Hematopoietic stem cell transplantation (HSCT) is a procedure performed in some people to treat certain blood or bone marrow cancers. Immediately before an HSCT procedure, a patient receives chemotherapy. Hepatic VOD can occur in people who receive chemotherapy and HSCT. Hepatic VOD is a condition in which some of the veins in the liver become blocked, causing swelling and a decrease in blood flow inside the liver, which may lead to liver damage. In the most severe form of hepatic VOD, the patient may also develop failure of the kidneys and lungs. Fewer than two percent of people develop severe hepatic VOD after HSCT, but as many as 80 percent of people who develop severe hepatic VOD do not survive.It is administered by intravenous infusion in a doctors office or clinic.

Contraindications
Use of defibrotide for people who are already taking anticoagulants is dangerous and use of other drugs that affect platelet aggregation, like NSAIDs, should be done with care.  Defibrotide should not be given to people who have a difficult time maintaining a steady blood pressure.

Adverse effects
There is a high risk of bleeding and some people have had hypersensitivity reactions to defibrotide.Common adverse effects, occurring in between 1 and 10% of people, included impaired blood clotting, vomiting, low blood pressure, bleeding in the brain, eyes, lungs, stomach or intestines, in the urine, and at catheterization sites.Other side effects have included diarrhea, nosebleeds, sepsis, graft vs host disease, and pneumonia.Pregnant women should not take defibrotide and women should not become pregnant while taking it; it has not been tested in pregnant women but at normal doses it caused hemolytic abortion in rats.

Pharmacology
Defibrotides mechanism of action is poorly understood. In vitro studies have shown that it protects the endothelium lining blood vessels from damage by fludarabine, a chemotherapy drug, and from a few other insults like serum starvation. It also appears to increase t-PA function and decrease plasminogen activator inhibitor-1 activity.

Chemistry
Defibrotide is a mixture of single-stranded oligonucleotides. The chemical name is polydeoxyribonucleotide, sodium salt.  It is purified from the intestinal mucosa of pigs.

History
The efficacy of defibrotide was investigated in 528 participants treated in three studies: two prospective clinical trials and an expanded access study. The participants enrolled in all three studies had a diagnosis of hepatic VOD with liver or kidney abnormalities after hematopoietic stem cell transplantation (HSCT). The studies measured the percentage of participants who were still alive 100 days after HSCT (overall survival). In the three studies, 38 to 45 percent of participants treated with defibrotide were alive 100 days after HSCT. Based on published reports and analyses of participant-level data, the expected survival rates 100 days after HSCT would be 21 to 31 percent for participants with severe hepatic VOD who received only supportive care or interventions other than defibrotide.

Society and culture
Legal status
Defibrotide was approved in the European Union for use in treating veno-occlusive disease of the liver of people having had a bone marrow transplant in 2013; Gentium had developed it.  At the end of that year, Jazz Pharmaceuticals acquired Gentium.In March 2016, the U.S. Food and Drug Administration (FDA) approved it for a similar use. Defibrotide is the first FDA-approved therapy for treatment of severe hepatic VOD, a rare and life-threatening liver condition. The FDA granted the application for defibrotide priority review status and orphan drug designation. The FDA granted approval of  Defitelio to Jazz Pharmaceuticals.Defibrotide was approved for medical use in Japan in June 2019.Defibrotide was approved for medical use in Australia in July 2020.

References
Further reading
Richardson P, Aggarwal S, Topaloglu O, Villa KF, Corbacioglu S (December 2019). "Systematic review of defibrotide studies in the treatment of veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS)". Bone Marrow Transplant. 54 (12): 1951–1962. doi:10.1038/s41409-019-0474-8. PMC 6957462 </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Diphenhydramine and can you explain it in depth? [/INST] Diphenhydramine (DPH) is an antihistamine medication mainly used to treat allergies. It can also be used for insomnia, symptoms of the common cold, tremor in parkinsonism, and nausea. It is taken by mouth, injected into a vein, injected into a muscle, or applied to the skin. Maximal effect is typically around two hours after a dose, and effects can last for up to seven hours.Common side effects include sleepiness, poor coordination and an upset stomach. Its use is not recommended in young children or the elderly. There is no clear risk of harm when used during pregnancy; however, use during breastfeeding is not recommended. It is a first generation H1-antihistamine and ethanolamine and works by blocking certain effects of histamine. Diphenhydramine is also a potent anticholinergic, and works as a deliriant at higher than recommended doses as a result. This has led to some cases of recreational use and addiction.Diphenhydramine was first made by George Rieveschl and came into commercial use in 1946. It is available as a generic medication. It is sold under the brand name Benadryl, among others. In 2017, it was the 241st most commonly prescribed medication in the United States, with more than two million prescriptions.

Medical uses
Diphenhydramine is a first-generation antihistamine used to treat a number of conditions including allergic symptoms and itchiness, the common cold, insomnia, motion sickness, and extrapyramidal symptoms. Diphenhydramine also has local anesthetic properties, and has been used as such in people allergic to common local anesthetics such as lidocaine.

Allergies
Diphenhydramine is effective in treatment of allergies. As of 2007, it was the most commonly used antihistamine for acute allergic reactions in the emergency department.By injection it is often used in addition to epinephrine for anaphylaxis, although as of 2007 its use for this purpose had not been properly studied. Its use is only recommended once acute symptoms have improved.

Topical formulations of diphenhydramine are available, including creams, lotions, gels, and sprays. These are used to relieve itching and have the advantage of causing fewer systemic effects (e.g., drowsiness) than oral forms.

Movement disorders
Diphenhydramine is used to treat akathisia and Parkinsons disease–like extrapyramidal symptoms caused by antipsychotics. It is also used to treat acute dystonia including torticollis and oculogyric crisis caused by first generation antipsychotics.

Sleep
Because of its sedative properties, diphenhydramine is widely used in nonprescription sleep aids for insomnia. The drug is an ingredient in several products sold as sleep aids, either alone or in combination with other ingredients such as acetaminophen (paracetamol) in Tylenol PM or ibuprofen in Advil PM. Diphenhydramine can cause minor psychological dependence. Diphenhydramine has also been used as an anxiolytic.Diphenhydramine has also been used off prescription by parents in an attempt to make their children sleep or remain sedated on long-distance flights. This has been met with criticism, both by doctors and members of the airline industry, as sedating young passengers may put them at risk if the flight encounters an emergency and they are unable to react to the situation efficiently, and the drugs side effects, especially the chance of a paradoxical reaction, may result in some individuals becoming hyperactive rather than sedated. The ethics of this use have also been challenged, with the Seattle Childrens hospital arguing in a 2009 article that "Using a medication for your convenience is never an indication for medication in a child."The American Academy of Sleep Medicines 2017 clinical practice guidelines recommended against the use of diphenhydramine in the treatment of insomnia due to poor effectiveness and low quality of evidence. A major systematic review and network meta-analysis of medications for the treatment of insomnia published in 2022 found little evidence to inform the use of diphenhydramine for insomnia.

Nausea
Diphenhydramine also has antiemetic properties, which make it useful in treating the nausea that occurs in vertigo and motion sickness.

Special populations
Diphenhydramine is not recommended for people older than 60 or children under the age of six, unless a physician is consulted. These populations should be treated with second-generation antihistamines such as loratadine, desloratadine, fexofenadine, cetirizine, levocetirizine, and azelastine. Due to its strong anticholinergic effects, diphenhydramine is on the Beers list of drugs to avoid in the elderly.Diphenhydramine is category B in the FDA Classification of Drug Safety During Pregnancy. It is also excreted in breast milk. It is expected that low doses of diphenhydramine taken occasionally will not cause any adverse effects on breastfed infants. Large doses or long-term use may affect the baby or reduce breast milk supply, especially when combined with sympathomimetic drugs such as pseudoephedrine or before the establishment of lactation. A single bedtime dose after the last feeding of the day may minimize any harmful effects of the medication on the baby and on the milk supply. Still, non-sedating antihistamines are the preferred alternative.Paradoxical reactions to diphenhydramine have been documented, in particular among children, and it may cause excitation instead of sedation.Topical diphenhydramine is sometimes used especially for people in hospice. This use is without indication and topical diphenhydramine should not be used as treatment for nausea because research does not indicate this therapy is more effective than alternatives.There were no documented cases of clinically apparent acute liver injury caused by normal doses of diphenhydramine.

Adverse effects
The most prominent side effect is sedation. A typical dose creates driving impairment equivalent to a blood-alcohol level of 0.10, which is higher than the 0.08 limit of most drunk-driving laws.Diphenhydramine is a potent anticholinergic agent and potential deliriant in higher doses. This activity is responsible for the side effects of dry mouth and throat, increased heart rate, pupil dilation, urinary retention, constipation, and, at high doses, hallucinations or delirium. Other side effects include motor impairment (ataxia), flushed skin, blurred vision at nearpoint owing to lack of accommodation (cycloplegia), abnormal sensitivity to bright light (photophobia), sedation, difficulty concentrating, short-term memory loss, visual disturbances, irregular breathing, dizziness, irritability, itchy skin, confusion, increased body temperature (in general, in the hands and/or feet), temporary erectile dysfunction, and excitability, and although it can be used to treat nausea, higher doses may cause vomiting. Diphenhydramine in overdose may occasionally result in QT prolongation.Some individuals experience an allergic reaction to diphenhydramine in the form of hives.Conditions such as restlessness or akathisia can worsen from increased levels of diphenhydramine, especially with recreational dosages. Normal doses of diphenhydramine, like other first generation antihistamines, can also make symptoms of restless legs syndrome worse.
As diphenhydramine is extensively metabolized by the liver, caution should be exercised when giving the drug to individuals with hepatic impairment.
Anticholinergic use later in life is associated with an increased risk for cognitive decline and dementia among older people.

Contraindications
Diphenhydramine is contraindicated in premature infants and neonates as well as people who are breastfeeding. It is a pregnancy Category B drug. Diphenhydramine has additive effects with alcohol and other CNS depressants. Monoamine Oxidase inhibitors prolong and intensify the anticholinergic effect of antihistamines.

Overdose
Diphenhydramine is one of the most commonly misused over-the-counter drugs in the United States. In cases of extreme overdose, if not treated in time, acute diphenhydramine poisoning may have serious and potentially fatal consequences. Overdose symptoms may include:

Acute poisoning can be fatal, leading to cardiovascular collapse and death in 2–18 hours, and in general is treated using a symptomatic and supportive approach. Diagnosis of toxicity is based on history and clinical presentation, and in general specific levels are not useful. Several levels of evidence strongly indicate diphenhydramine (similar to chlorpheniramine) can block the delayed rectifier potassium channel and, as a consequence, prolong the QT interval, leading to cardiac arrhythmias such as torsades de pointes.
No specific antidote for diphenhydramine toxicity is known, but the anticholinergic syndrome has been treated with physostigmine for severe delirium or tachycardia. Benzodiazepines may be administered to decrease the likelihood of psychosis, agitation, and seizures in people who are prone to these symptoms.

Interactions
Alcohol may increase the drowsiness caused by diphenhydramine.

Pharmacology
Pharmacodynamics
Diphenhydramine, while traditionally known as an antagonist, acts primarily as an inverse agonist of the histamine H1 receptor. It is a member of the ethanolamine class of antihistaminergic agents. By reversing the effects of histamine on the capillaries, it can reduce the intensity of allergic symptoms. It also crosses the blood–brain barrier and inversely agonizes the H1 receptors centrally. Its effects on central H1 receptors cause drowsiness.
Like many other first-generation antihistamines, diphenhydramine is also a potent antimuscarinic (a competitive antagonist of muscarinic acetylcholine receptors) and, as such, at high doses can cause anticholinergic syndrome. The utility of diphenhydramine as an antiparkinson agent is the result of its blocking properties on the muscarinic acetylcholine receptors in the brain.
Diphenhydramine also acts as an intracellular sodium channel blocker, which is responsible for its actions as a local anesthetic. Diphenhydramine has also been shown to inhibit the reuptake of serotonin. It has been shown to be a potentiator of analgesia induced by morphine, but not by endogenous opioids, in rats. The drug has also been found to act as an inhibitor of histamine N-methyltransferase (HNMT).

Pharmacokinetics
Oral bioavailability of diphenhydramine is in the range of 40% to 60%, and peak plasma concentration occurs about 2 to 3 hours after administration.The primary route of metabolism is two successive demethylations of the tertiary amine. The resulting primary amine is further oxidized to the carboxylic acid. Diphenhydramine is metabolized by the cytochrome P450 enzymes CYP2D6, CYP1A2, CYP2C9, and CYP2C19.The elimination half-life of diphenhydramine has not been fully elucidated, but appears to range between 2.4 and 9.3 hours in healthy adults. A 1985 review of antihistamine pharmacokinetics found that the elimination half-life of diphenhydramine ranged between 3.4 and 9.3 hours across five studies, with a median elimination half-life of 4.3 hours. A subsequent 1990 study found that the elimination half-life of diphenhydramine was 5.4 hours in children, 9.2 hours in young adults, and 13.5 hours in the elderly. A 1998 study found a half-life of 4.1 ± 0.3 hours in young men, 7.4 ± 3.0 hours in elderly men, 4.4 ± 0.3 hours in young women, and 4.9 ± 0.6 hours in elderly women. In a 2018 study in children and adolescents, the half-life of diphenhydramine was 8 to 9 hours.

Chemistry
Diphenhydramine is a diphenylmethane derivative. Analogues of diphenhydramine include orphenadrine, an anticholinergic, nefopam, an analgesic, and tofenacin, an antidepressant.

Detection in body fluids
Diphenhydramine can be quantified in blood, plasma, or serum. Gas chromatography with mass spectrometry (GC-MS) can be used with electron ionization on full scan mode as a screening test. GC-MS or GC-NDP can be used for quantification. Rapid urine drug screens using immunoassays based on the principle of competitive binding may show false-positive methadone results for people having ingested diphenhydramine. Quantification can be used to monitor therapy, confirm a diagnosis of poisoning in people who are hospitalized, provide evidence in an impaired driving arrest, or assist in a death investigation.

History
Diphenhydramine was discovered in 1943 by George Rieveschl, a former professor at the University of Cincinnati. In 1946, it became the first prescription antihistamine approved by the U.S. FDA.In the 1960s, diphenhydramine was found to weakly inhibit reuptake of the neurotransmitter serotonin. This discovery led to a search for viable antidepressants with similar structures and fewer side effects, culminating in the invention of fluoxetine (Prozac), a selective serotonin reuptake inhibitor (SSRI). A similar search had previously led to the synthesis of the first SSRI, zimelidine, from brompheniramine, also an antihistamine.

Society and culture
Diphenhydramine is deemed to have limited abuse potential in the United States owing to its potentially serious side-effect profile and limited euphoric effects, and is not a controlled substance. Since 2002, the U.S. FDA has required special labeling warning against use of multiple products that contain diphenhydramine. In some jurisdictions, diphenhydramine is often present in postmortem specimens collected during investigation of sudden infant deaths; the drug may play a role in these events.Diphenhydramine is among prohibited and controlled substances in the Republic of Zambia, and travelers are advised not to bring the drug into the country. Several Americans have been detained by the Zambian Drug Enforcement Commission for possession of Benadryl and other over-the-counter medications containing diphenhydramine.

Recreational use
Although diphenhydramine is widely used and generally considered to be safe for occasional usage, multiple cases of abuse and addiction have been documented </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Birth control pill formulations and can you explain it in depth? [/INST] Birth control pills come in a variety of formulations. The main division is between combined oral contraceptive pills, containing both estrogens and synthetic progestogens (progestins), and progestogen only pills. Combined oral contraceptive pills also come in varying types, including varying doses of estrogen, and whether the dose of estrogen or progestogen changes from week to week.

Mechanism of action
Combination pills usually work by preventing the ovaries from releasing eggs (ovulation). They also thicken the cervical mucus, which keeps sperm from penetrating into the uterus and joining with an egg. The hormones in combination and progestogen-only pills also thin the lining of the uterus. This could prevent pregnancy by interfering with implantation of a blastocyst.
Main action in typical use is prevention of ovulation.

Combined oral contraceptive pills
All contain an estrogen, ethinylestradiol or mestranol, in varying amounts, and one of a number of different progestogens </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Azacitidine and can you explain it in depth? [/INST] Azacitidine, sold under the brand name Vidaza among others, is used for the treatment of myelodysplastic syndrome, myeloid leukemia, and juvenile myelomonocytic leukemia. It is a chemical analog of cytidine, a nucleoside in DNA and RNA. Azacitidine and its deoxy derivative, decitabine (also known as 5-aza-2′-deoxycytidine) were first synthesized in Czechoslovakia as potential chemotherapeutic agents for cancer.The most common adverse reactions in children with juvenile myelomonocytic leukemia include pyrexia, rash, upper respiratory tract infection, and anemia.

Medical uses
Azacitidine is indicated for the treatment of myelodysplastic syndrome, for which it received approval by the U.S. Food and Drug Administration (FDA) on May 19, 2004. In two randomized controlled trials comparing azacitidine to supportive treatment, 16% of subjects with myelodysplastic syndrome who were randomized to receive azacitidine had a complete or partial normalization of blood cell counts and bone marrow morphology, compared to none who received supportive care, and about two-thirds of patients who required blood transfusions no longer needed them after receiving azacitidine.Azacitidine is also indicated for the treatment of myeloid leukemia and juvenile myelomonocytic leukemia.

Mechanism of action
Azacitidine is a chemical analogue of the nucleoside cytidine, which is present in DNA and RNA. It is thought to have antineoplastic activity via two mechanisms – at low doses, by inhibiting of DNA methyltransferase, causing hypomethylation of DNA, and at high doses, by its direct cytotoxicity to abnormal hematopoietic cells in the bone marrow through its incorporation into DNA and RNA, resulting in cell death. Azacitidine is a ribonucleoside, so it is incorporated into RNA to a larger extent than into DNA. In contrast, decitabine (5-aza-2-deoxycytidine) is a deoxyribonucleoside, so it can only incorporate into DNA. Azacitidines incorporation into RNA leads to the disassembly of polyribosomes, defective methylation and acceptor function of transfer RNA, and inhibition of the production of proteins. Its incorporation into DNA leads to covalent binding with DNA methyltransferases, which prevents DNA synthesis and subsequently leads to cytotoxicity. It has been shown effective against human immunodeficiency virus in vitro and human T-lymphotropic virus.

Inhibition of methylation
After azanucleosides such as azacitidine have been metabolized to 5-aza-2′-deoxycytidine-triphosphate (aka, decitabine-triphosphate), they can be incorporated into DNA and azacytosine can be substituted for cytosine. Azacytosine-guanine dinucleotides are recognized as substrate by the DNA methyltransferases, which catalyze the methylation reaction by a nucleophilic attack. This results in a covalent bond between the carbon-6 atom of the cytosine ring and the enzyme. The bond is normally resolved by beta-elimination through the carbon-5 atom, but this latter reaction does not occur with azacytosine because its carbon-5 is substituted by nitrogen, leaving the enzyme covalently bound to DNA and blocking its DNA methyltransferase function. In addition, the covalent protein adduction also compromises the functionality of DNA and triggers DNA damage signaling, resulting in the degradation of trapped DNA methyltransferases. As a consequence, methylation marks become lost during DNA replication.

Toxicity
Azacitidine causes anemia (low red blood cell counts), neutropenia (low white blood cell counts), and thrombocytopenia (low platelet counts), and patients should have frequent monitoring of their complete blood counts, at least prior to each dosing cycle. The dose may have to be adjusted based on nadir counts and hematologic response.It can also be hepatotoxic in patients with severe liver impairment, and patients with extensive liver tumors due to metastatic disease have developed progressive hepatic coma and death during azacitidine treatment, especially when their albumin levels are less than 30 g/L </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Serostim and can you explain it in depth? [/INST]  </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Loxapine and can you explain it in depth? [/INST] Loxapine, sold under the brand names Loxitane and Adasuve (inhalation only) among others, is an antipsychotic medication used primarily in the treatment of schizophrenia. The medicine is a member of the dibenzoxazepine class and structurally very similar to clozapine. Several researchers have argued that loxapine, initially classified as a typical antipsychotic, behaves as an atypical antipsychotic.Loxapine may be metabolized by N-demethylation to amoxapine, a tricyclic antidepressant.

Medical uses
The US Food and Drug Administration (FDA) has approved loxapine inhalation powder for the acute treatment of agitation associated with schizophrenia or bipolar I disorder in adults.A brief review of loxapine found no conclusive evidence that it was particularly effective in patients with schizophrenia. A subsequent systematic review considered that the limited evidence did not indicate a clear difference in its effects from other antipsychotics.

Available forms
Loxapine can be taken by mouth. It is also available as an intramuscular injection and as a powder for inhalation.

Side effects
Loxapine can cause side effects that are generally similar to that of other antipsychotic medications. These include, e.g., gastrointestinal problems (like constipation and abdominal pain), cardiovascular problems (like tachycardia), moderate likelihood of drowsiness (relative to other antipsychotics), and movement problems (i.e. extrapyramidal symptoms [EPS]). At lower dosages its propensity for causing EPS appears to be similar to that of atypical antipsychotics </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Dalbavancin and can you explain it in depth? [/INST] Dalbavancin, sold under the brand names Dalvance in the US and Xydalba in the EU among others, is a second-generation lipoglycopeptide antibiotic medication. It belongs to the same class as vancomycin, the most widely used and one of the treatments available to people infected with methicillin-resistant Staphylococcus aureus (MRSA).Dalbavancin is a semisynthetic lipoglycopeptide that was designed to improve upon the natural glycopeptides vancomycin and teicoplanin. It is derived from a complex of glycopeptide antibiotics, referred to as A-40926, that is produced by a new strain of Actinomadura. Dalbavancin has been referred to in the scientific literature by a series of names: MDL-63397, A-!-1, BI-397, VER-001. These different labels reflected where the research had been carried out: MDL representing Merrell-Dow-Lepetit, where the initial complex was discovered; BI referring to BioSearch Italia where Dalbavancin itself  was first synthesized; VER referring to Versicor (which Biosearch Italia merged with to create Vicuron Pharmaceuticals). The phase I, II and III clinical trials were carried out of by Vicuron and the initial NDA filed. Vicuron was acquired by Pfizer in 2005, which decided to not further develop Dalbavancin at that time, subsequently selling the rights to Durata Therapeutics in 2009.It possesses in vitro activity against a variety of Gram-positive pathogens including MRSA and methicillin-resistant Staphylococcus epidermidis (MRSE). It is a once-weekly, two-dose antibiotic, the rights to which Actavis acquired when it bought Durata Therapeutics in 2014.The U.S. Food and Drug Administration (FDA) approved dalbavancin in May 2014, for the treatment of acute bacterial skin and skin structure infections (ABSSSIs) caused by certain susceptible bacteria such as Staphylococcus aureus including methicillin-susceptible and methicillin-resistant strains of Streptococcus pyogenes, in intravenous dosage form.

Medical uses
Dalbavancin is an antibiotic used to treat acute bacterial skin and skin structure infections (ABSSSI) in adults caused by susceptible Gram-positive organisms, including methicillin-resistant Staphylococcus aureus (MRSA).  MRSA infections have become problematic in the community and in healthcare settings due to resistance to many available antibiotics. Because dalbavancin has demonstrated efficacy against MRSA and other microorganisms to treat serious or life-threatening infections, it was the first drug approved as a Qualified Infectious Disease Product under the Generating Antibiotic Incentives Now (GAIN) act, which is part of the FDA Safety and Innovation Act.It has strong activity against many Gram-positive bacteria, including methicillin-sensitive and methicillin-resistant Staphylococcus aureus, Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus anginosus, Streptococcus intermedius, and Streptococcus constellatus. Based on MIC data and other studies, dalbavancin is more potent and bactericidal and therefore requires lower concentrations than vancomycin against these organisms. Dalbavancin also shows in vitro activity against vancomycin-susceptible Enterococcus faecium and Enterococcus faecalis.  Other Gram-positive organisms belonging to the Bacillus spp., Listeria spp., and Corynebacterium spp. may show in vitro susceptibility, and dalbavancin may exhibit activity against enterococci expressing the VanB or VanC phenotype of acquired resistance against vancomycin.  There is no clinically significant activity against Gram-negative bacteria.Two trials, DISCOVER 1 and DISCOVER 2, demonstrated noninferiority of dalbavancin compared to vancomycin/linezolid in the treatment of ABSSSI.  Patients were randomly assigned to receive two doses of dalbavancin on days 1 and 8, or to receive intravenous vancomycin for at least 3 days with the option of switching to oral linezolid to complete 10 to 14 days of therapy.  Investigators assessed the cessation of spread of infection-related erythema and the absence of fever at 48 to 72 hours as the primary endpoint and found that once-weekly dalbavancin was as effective as twice-daily intravenous vancomycin followed by oral linezolid.  This once-weekly dosing regimen may offer an advantageous treatment option compared to daily or twice-daily dosing.

Contraindications
Hypersensitivity to dalbavancin can occur, causing issues such as skin reactions or anaphylaxis. Caution is advised for patients with known hypersensitivity to other glycopeptides.  There is currently no data on cross-reactivity between dalbavancin and vancomycin.

Side effects
The most common adverse reactions encountered in Phase II and Phase III trials were nausea (5.5%), headache (4.7%), and diarrhea (4.4%), as well as rash (2.7%) and itchiness (2.1%).  Other less frequent but serious adverse reactions included hematologic disorders, hepatotoxicity, Clostridium difficile colitis, bronchospasm, infusion-related reactions including Red Man Syndrome, and anaphylactic shock.  In trials, dalbavancin was associated with higher rates of hemorrhagic events compared to comparator groups and should be a precaution in patients undergoing surgery or taking anticoagulants.  Patients on dalbavancin also had post-baseline alanine aminotransferase (ALT) levels that were 3 times the upper normal limit, some even having elevations 10 times the upper normal limit; however, eight of the twelve dalbavancin-treated patients had comorbid conditions that could affect their ALT, compared to only one patient in the comparator group.  There is no evidence of ototoxicity associated with dalbavancin.

Drug interactions
Clinical drug-drug interactions with dalbavancin have not been studied, and dalbavancin does not appear to interact with cytochrome P450 substrates, inhibitors, or inducers. It was found to have an in vitro synergistic interaction with the antimicrobial oxacillin, but the clinical significance of this interaction has yet to be established.

Pregnancy and lactation
Use of dalbavancin in pregnant women has not been studied sufficiently and should only occur when the potential benefit outweighs the potential risk to the fetus.  Animal studies did not show embryo or fetal toxicity at doses that were 1.2 and 0.7 times the human dose.  However, delayed fetal maturation was observed at a dose that was 3.5 times the human dose.  While dalbavancin is excreted in rat milk, it is unknown if it is excreted in human milk.  It should be used in nursing mothers only when the potential benefit exceeds the potential risk.  There is no evidence in animals of teratogenicity.

Production and composition
Dalbavancin is manufactured by fermentation of a selected Nonomuraea strain to generate the natural glycopeptide complex A-40926. This precursor is then selectively esterified at the carboxyl group of its sugar moiety, its peptidyl carboxyl group is amidated
and the ester of the N-acylaminoglucuronic acid carboxyl group is saponified. The outcome is a compound mixture of two closely related structural families — A and B — that can be further subdivided into a total of five subtypes (see table below). At least ten different dalbavancin components have been described, of which the B0 component makes up around 80–98 wt%.

Mechanism of action
Dalbavancin is a lipoglycopeptide belonging in the same glycopeptide class as vancomycin.  Similar to other glycopeptides, dalbavancin exerts its bactericidal effect by disrupting cell wall biosynthesis </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Pegasys and can you explain it in depth? [/INST]  </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Phytomenadione and can you explain it in depth? [/INST] Phytomenadione, also known as  vitamin K1 or phylloquinone, is a vitamin  found in food and used as a dietary supplement. It is on the World Health Organizations List of Essential Medicines.As a supplement it is used to treat certain bleeding disorders. This includes warfarin overdose, vitamin K deficiency, and obstructive jaundice. It is also recommended to prevent and treat vitamin K deficiency bleeding in infants. Use is typically recommended by mouth, intramuscular injection or injection under the skin. When given by injection benefits are seen within two hours. Many countries in the world choose intramuscular injections in newborn to keep them safe from severe bleeding (VKDB). It is considered a safe treatment and saves many children from death and severe neurologic deficit every year.Side effects when given by injection may include pain at the site of injection. Severe allergic reactions may occur when it is injected into a vein or muscle, but this has mainly happened when large doses of a certain type of supplement containing castor oil were given intravenously. Use during pregnancy is considered safe, use is also likely okay during breastfeeding. It works by supplying a required component for making a number of blood clotting factors. Found sources include green vegetables, vegetable oil, and some fruit.Phytomenadione was first isolated in 1939. In 1943 Edward Doisy and Henrik Dam were given a Nobel Prize for its discovery.

Terminology
Phytomenadione is often also called phylloquinone, vitamin K, or phytonadione.
A stereoisomer of phylloquinone is called vitamin k1 (note the difference in capitalization).

Chemistry
Vitamin K is a fat-soluble vitamin that is stable in air and moisture but decomposes in sunlight </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Mefloquine and can you explain it in depth? [/INST] Mefloquine, sold under the brand name Lariam among others, is a medication used to prevent or treat malaria. When used for prevention it is typically started before potential exposure and continued for several weeks after potential exposure. It can be used to treat mild or moderate malaria but is not recommended for severe malaria. It is taken by mouth.Common side effects include vomiting, diarrhea, headaches, sleep disorders, and a rash. Serious side effects include potentially long-term mental health problems such as depression, hallucinations, and anxiety and neurological side effects such as poor balance, seizures, and ringing in the ears. It is therefore not recommended in people with a history of mental health problems or epilepsy. It appears to be safe during pregnancy and breastfeeding.Mefloquine was developed by the United States Army in the 1970s and came into use in the mid-1980s. It is on the World Health Organizations List of Essential Medicines. It is available as a generic medication.

Medical uses
Mefloquine is used to both prevent and treat certain forms of malaria.

Malaria prevention
Mefloquine is useful for the prevention of malaria in all areas except for those where parasites may have resistance to multiple medications, and is one of several anti-malarial medications recommended by the United States Centers for Disease Control and Prevention for this purpose. It is also recommended by the Infectious Disease Society of America for malaria prophylaxis as a first or second-line agent, depending on resistance patterns in the malaria found in the geographic region visited. It is typically taken for one to two weeks before entering an area with malaria. Doxycycline and atovaquone/proguanil provide protection within one to two days and may be better tolerated. If a person becomes ill with malaria despite prophylaxis with mefloquine, the use of halofantrine and quinine for treatment may be ineffective.: 4

Malaria treatment
Mefloquine is used as a treatment for chloroquine-sensitive or resistant Plasmodium falciparum malaria, and is deemed a reasonable alternative for uncomplicated chloroquine-resistant Plasmodium vivax malaria. It is one of several drugs recommended by the United States Centers for Disease Control and Prevention.
It is not recommended for severe malaria infections, particularly infections from P. falciparum, which should be treated with intravenous antimalarials. Mefloquine does not eliminate parasites in the liver phase of the disease, and people with P. vivax malaria should be treated with a second drug that is effective for the liver phase, such as primaquine.: 4

Resistance to mefloquine
Resistance to mefloquine is common around the west border in Cambodia and other parts of Southeast Asia. The mechanism of resistance is by increase in Pfmdr1 copy number.

Adverse effects
Common side effects include vomiting, diarrhea, headaches, and a rash. Severe side effects requiring hospitalization are rare, but include mental health problems such as depression, hallucinations, anxiety and neurological side effects such as poor balance, seizures, and ringing in the ears. Mefloquine is therefore not recommended in people with a history of psychiatric disorders or epilepsy.

Neurologic and psychiatric
In 2013, the U.S. Food and Drug Administration (FDA) added a boxed warning to the prescription label of mefloquine regarding the potential for neuropsychiatric side effects that may persist even after discontinuing administration of the medication. In 2013 the FDA stated "Neurologic side effects can occur at any time during drug use, and can last for months to years after the drug is stopped or can be permanent." Neurologic effects include dizziness, loss of balance, seizures, and tinnitus. Psychiatric effects include nightmares, visual hallucinations, auditory hallucinations, anxiety, depression, unusual behavior, and suicidal ideations.
Central nervous system events requiring hospitalization occur in about one in 10,000 people taking mefloquine for malaria prevention, with milder events (e.g., dizziness, headache, insomnia, and vivid dreams) in up to 25%. When some measure of subjective severity is applied to the rating of adverse events, about 11–17% of travelers are incapacitated to some degree.

Cardiac
Mefloquine may cause abnormalities with heart rhythms that are visible on electrocardiograms. Combining mefloquine with other drugs that cause similar effects, such as quinine or quinidine, can increase these effects. Combining mefloquine with halofantrine can cause significant increases in QTc intervals.: 10

Contraindications
Mefloquine is contraindicated in those with a previous history of seizures or a recent history of psychiatric disorders.

Pregnancy and breastfeeding
Available data suggests that mefloquine is safe and effective for use by pregnant women during all trimesters of pregnancy, and it is widely used for this indication. In pregnant women, mefloquine appears to pose minimal risk to the fetus, and is not associated with increased risk of birth defects or miscarriages. Compared to other malaria chemoprophylaxis regimens, however, mefloqinone may produce more side effects in non-pregnant travelers.
Mefloquine is also safe and effective for use during breastfeeding, though it appears in breast milk in low concentrations.: 9  The World Health Organization (WHO) gives approval for the use of mefloquine in the second and third trimesters of pregnancy and use in the first trimester does not mandate termination of pregnancy.

Pharmacology
Elimination
Mefloquine is metabolized primarily through the liver. Its elimination in persons with impaired liver function may be prolonged, resulting in higher plasma levels and an increased risk of adverse reactions. The mean elimination plasma half-life of mefloquine is between two and four weeks. Total clearance is through the liver, and the primary means of excretion is through the bile and feces, as opposed to only 4% to 9% excreted through the urine. During long-term use, the plasma half-life remains unchanged.Liver function tests should be performed during long-term administration of mefloquine. Alcohol use should be avoided during treatment with mefloquine.

Chemistry
Specifically it is used as mefloquine hydrochloride.
Mefloquine is a chiral molecule with two asymmetric carbon centres, which means it has four different stereoisomers. The drug is currently manufactured and sold as a racemate of the (R,S)- and (S,R)-enantiomers by Hoffman-LaRoche, a Swiss pharmaceutical company. Essentially, it is two drugs in one. Plasma concentrations of the (–)-enantiomer are significantly higher than those for the (+)-enantiomer, and the pharmacokinetics between the two enantiomers are significantly different. The (+)-enantiomer has a shorter half-life than the (–)-enantiomer.

History
Mefloquine was formulated at Walter Reed Army Institute of Research (WRAIR) in the 1970s shortly after the end of the Vietnam war. Mefloquine was number 142,490 of a total of 250,000 antimalarial compounds screened during the study.Mefloquine was the first Public-Private Venture (PPV) between the US Department of Defense and a pharmaceutical company. WRAIR transferred all its phase I and phase II clinical trial data to Hoffman-LaRoche and Smith Kline. FDA approval as a treatment for malaria was swift. Most notably, phase III safety and tolerability trials were skipped.The drug was first approved in Switzerland in 1984 by Hoffmann-LaRoche, who brought it to market with the name Lariam.However, mefloquine was not approved by the FDA for prophylactic use until 1989. This approval was based primarily on compliance, while safety and tolerability were overlooked. Because of the drugs very long half-life, the Centers for Disease Control originally recommended a mefloquine dosage of 250 mg every two weeks; however, this caused an unacceptably high malaria rate in the Peace Corps volunteers who participated in the approval study, so the drug regimen was switched to once a week.By 1991, Hoffman was marketing the drug on a worldwide basis.By the 1992 UNITAF, Canadian soldiers were being prescribed the drug en masse.By 1994, medical professionals were noting "severe psychiatric side effects observed during prophylaxis and treatment with mefloquine", and recommending that "the absence of contraindications and minor side effects during an initial course of mefloquine should be confirmed before another course is prescribed." Other doctors at the University Hospital of Zurich noted in a case of "a 47-year-old, previously healthy Japanese tourist" who had severe neuropsychiatric side-effects from the drug that
The neuropsychiatric side effects of the antimalarial drug mefloquine are well documented. They include anxiety, depression, hallucinations, acute psychosis, and seizures. The incidence of these side effects is 1 in 13,000 with prophylactic use and 1 in 250 with therapeutic use.
The first randomized, controlled trial on a mixed population was performed in 2001. Prophylaxis with mefloquine was compared to prophylaxis with atovaquone-proguanil. Roughly 67% of participants in the mefloquine arm reported greater than or equal to one adverse event, vs 71% in the atovaquone-proguanil arm. In the mefloquine arm, 5% of the users reported severe events requiring medical attention, vs 1.2% in the atovaquone-proguanil arm.In August 2009, Roche stopped marketing Lariam in the United States.Retired soldier Johnny Mercer, who was later appointed Minister for Veterans Affairs by Boris Johnson, told in 2015 that he had received "a letter about once or twice a week" about ill-effects from the drug. In July 2016, Roche took this brand off the market in Ireland.

Military
In 2006, the Australian military deemed mefloquine "a third-line drug" alternative, and over the five years from 2011 only 25 soldiers had been prescribed the drug, and only in cases of their intolerance for other alternatives. Between 2001 and 2012, 16,000 Canadian soldiers sent to Afghanistan were given the drug as a preventative measure. In 2013, the US Army banned mefloquine from use by its special forces such as the Green Berets. In autumn 2016, the UK military followed suit with their Australian peers after a parliamentary inquiry into the matter revealed that it can cause permanent side effects and brain damage.In early December 2016, the German defence ministry removed mefloquine from the list of medications it would provide to its soldiers.In autumn 2016, Canadian Surgeon General Brigadier General Hugh Colin MacKay told a parliamentary committee that faulty science supported the assertion that the drug has indelible noxious side effects. An expert from Health Canada named Barbara Raymond told the same committee that the evidence she had read failed to support the conclusion of indelible side effects. Canadian soldiers who took mefloquine when deployed overseas have claimed they have been left with ongoing mental health problems.

Research
In June 2010, the first case report appeared of a progressive multifocal leukoencephalopathy being successfully treated with mefloquine. Mefloquine can also act against the JC virus. Administration of mefloquine seemed to eliminate the virus from the patients body and prevented further neurological deterioration.Mefloquine alters cholinergic synaptic transmission through both postsynaptic  and presynaptic actions. The postsynaptic action to inhibit acetylcholinesterase changes transmission across synapses in the brain.

References
Further reading
Chen LH, Wilson ME, Schlagenhauf P (May 2007). "Controversies and misconceptions in malaria chemoprophylaxis for travelers". JAMA. 297 (20): 2251–63. doi:10.1001/jama.297.20.2251. PMID 17519415.
Schlagenhauf P, Adamcova M, Regep L, Schaerer MT, Rhein HG (December 2010) </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Cefazolin and can you explain it in depth? [/INST] Cefazolin, also known as cefazoline and cephazolin, is a first-generation cephalosporin antibiotic used for the treatment of a number of bacterial infections. Specifically it is used to treat cellulitis, urinary tract infections, pneumonia, endocarditis, joint infection, and biliary tract infections. It is also used to prevent group B streptococcal disease around the time of delivery and before surgery. It is typically given by injection into a muscle or vein.Common side effects include diarrhea, vomiting, yeast infections, and allergic reactions. It is not recommended in people who have a history of anaphylaxis to penicillin. It is relatively safe for use during pregnancy and breastfeeding. Cefazolin is in the first-generation cephalosporin class of medication and works by interfering with the bacterias cell wall.Cefazolin was patented in 1967 and came into commercial use in 1971. It is on the World Health Organizations List of Essential Medicines. It is available as a generic medication.

Medical uses
Cefazolin is used in a variety of infections provided that susceptible organisms are involved. It is indicated for use in the following infections:
Respiratory tract infections
Urinary tract infections
Skin infections
Biliary tract infections
Bone and joint infections
Genital infections
Blood infections (sepsis)
EndocarditisIt can also be used peri-operatively to prevent infections post-surgery, and is often the preferred drug for surgical prophylaxis.There is no penetration into the central nervous system and therefore cefazolin is not effective in treating meningitis.Cefazolin has been shown to be effective in treating methicillin-susceptible Staphylococcus aureus (MSSA) but does not work in cases of methicillin-resistant Staphylococcus aureus (MRSA). In many instances of staphylococcal infections, such as bacteremia, cefazolin is an alternative to penicillin in patients who are allergic to penicillin. However, there is still potential for a reaction to occur with cefazolin and other cephalosporins in patients allergic to penicillin. Resistance to cefazolin is seen in several species of bacteria, such as Mycoplasma and Chlamydia, in which case different generations of cephalosporins may be more effective. Cefazolin does not fight against Enterococcus, anaerobic bacteria or atypical bacteria among others.

Bacterial susceptibility
As a first-generation cephalosporin antibiotic, cefazolin and other first-generation antibiotics are very active against gram-positive bacteria and some gram-negative bacteria. Their broad spectrum of activity can be attributed to their improved stability to many bacterial beta-lactamases compared to penicillins.

Spectrum of activity
Gram-positive aerobes:
Staphylococcus aureus (including beta-lactamase producing strains)
Staphylococcus epidermidis
Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus pneumoniae and  other strains of streptococciGram-Negative Aerobes:

Escherichia coli
Proteus mirabilis

Non susceptible
The following are not susceptible:
Methicillin-resistant staphylococcus aureus
Enterococcus
most strains of indole positive Proteus (Proteus vulgaris)
Enterobacter spp.
Morganella morganii
Providencia rettgeri
Serratia spp.
Pseudomonas spp.
Listeria

Special populations
Pregnancy
Cefazolin is pregnancy category B, indicating general safety for use in pregnancy. Caution should be used in breastfeeding as a small amount of cefazolin enters the breast milk. Cefazolin can be used prophylactically against perinatal Group B streptococcal infection (GBS). Although penicillin and ampicillin are the standard of care for GBS prophylaxis, penicillin-allergic women with no history of anaphylaxis can be given cefazolin instead </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Zidovudine and can you explain it in depth? [/INST] Zidovudine (ZDV), also known as azidothymidine (AZT), is an antiretroviral medication used to prevent and treat HIV/AIDS. It is generally recommended for use in combination with other antiretrovirals. It may be used to prevent mother-to-child spread during birth or after a needlestick injury or other potential exposure. It is sold both by itself and together as lamivudine/zidovudine and abacavir/lamivudine/zidovudine. It can be used by mouth or by slow injection into a vein.Common side effects include headaches, fever, and nausea. Serious side effects include liver problems, muscle damage, and high blood lactate levels. It is commonly used in pregnancy and appears to be safe for the baby. ZDV is of the nucleoside analog reverse-transcriptase inhibitor (NRTI) class. It works by inhibiting the enzyme reverse transcriptase that HIV uses to make DNA and therefore decreases replication of the virus.Zidovudine was first described in 1964. It was approved in the United States in 1987 and was the first treatment for HIV. It is on the World Health Organizations List of Essential Medicines. It is available as a generic medication.

Medical uses
HIV treatment
AZT is usually dosed twice a day in combination with other antiretroviral therapies. This approach is referred to as Highly Active Antiretroviral Therapy (HAART) and is used to prevent the likelihood of HIV resistance.

HIV prevention
AZT has been used for post-exposure prophylaxis (PEP) in combination with another antiretroviral drug called lamivudine. Together they work to substantially reduce the risk of HIV infection following the first single exposure to the virus. More recently, AZT has been replaced by other antiretrovirals such as tenofovir to provide PEP.AZT is now a principal part of the clinical pathway for both pre-exposure prophylaxis and post-exposure treatment of mother-to-child transmission of HIV during pregnancy, labor, and delivery and has been proven to be integral to uninfected siblings perinatal and neonatal development. Without AZT, 10 to 15% of fetuses with HIV-infected mothers will themselves become infected. AZT has been shown to reduce this risk to 8% when given in a three-part regimen post-conception, delivery, and six weeks post-delivery. Consistent and proactive precautionary measures, such as the rigorous use of antiretroviral medications, cesarean section, face masks, heavy-duty rubber gloves, clinically segregated disposable diapers, and avoidance of mouth contact will further reduce child-attendant transmission of HIV to as little as 1–2%.During 1994 to 1999, AZT was the primary form of prevention of mother-to-child HIV transmission. AZT prophylaxis prevented more than 1000 parental and infant deaths from AIDS in the United States. In the U.S. at that time, the accepted standard of care for HIV-positive mothers was known as the 076 regimen and involved five daily doses of AZT from the second trimester onwards, as well as AZT intravenously administered during labour. As this treatment was lengthy and expensive, it was deemed unfeasible in the Global South, where mother-to-child transmission was a significant problem. A number of studies were initiated in the late 1990s that sought to test the efficacy of a shorter, simpler regimen for use in resource-poor countries. This AZT short course was an inferior standard of care and would have been considered malpractice if trialed in the US; however, it was nonetheless a treatment that would improve the care and survival of impoverished subjects.

Antibacterial properties
Zidovudine also has antibacterial properties, though not routinely used in clinical settings. It acts on bacteria with a mechanism of action still not fully explained. Promising results from in vitro and in vivo studies showed the efficacy of AZT also against multidrug-resistant gram-negative bacteria (including mcr-1 carrying and metallo-β-lactamase producing isolates), especially in combination with other active agents (e.g. fosfomycin, colistin, tigecycline).

Side effects
Most common side-effects include nausea, vomiting, acid reflux (heartburn), headache, cosmetic reduction in abdominal body fat, light sleeping, and loss of appetite. Less common side effects include faint discoloration of fingernails and toenails, mood elevation, occasional tingling or transient numbness of the hands or feet, and minor skin discoloration. Allergic reactions are rare.Early long-term higher-dose therapy with AZT was initially associated with side effects that sometimes limited therapy, including anemia, neutropenia, hepatotoxicity, cardiomyopathy, and myopathy. All of these conditions were generally found to be reversible upon reduction of AZT dosages. They have been attributed to several possible causes, including transient depletion of mitochondrial DNA, sensitivity of the γ-DNA polymerase in some cell mitochondria, the depletion of thymidine triphosphate, oxidative stress, reduction of intracellular L-carnitine or apoptosis of the muscle cells. Anemia due to AZT was successfully treated using erythropoetin to stimulate red blood cell production. Drugs that inhibit hepatic glucuronidation, such as indomethacin, nordazepam, acetylsalicylic acid (aspirin) and trimethoprim decreased the elimination rate and increased the therapeutic strength of the medication. Today, side-effects are much less common with the use of lower doses of AZT.
According to IARC, there is sufficient evidence in experimental animals for the carcinogenicity of zidovudine; it is possibly carcinogenic to humans (Group 2B). In 2009, the State of California added zidovudine to its list of chemicals "known to the state of California to cause cancer and other reproductive harm."

Viral resistance
Even at the highest doses that can be tolerated in patients, AZT is not potent enough to prevent all HIV replication and may only slow the replication of the virus and progression of the disease. Prolonged AZT treatment can lead to HIV developing resistance to AZT by mutation of its reverse transcriptase. To slow the development of resistance, physicians generally recommend that AZT be given in combination with another reverse-transcriptase inhibitor and an antiretroviral from another group, such as a protease inhibitor, non-nucleoside reverse-transcriptase inhibitor, or integrase inhibitor; this type of therapy is known as HAART (Highly Active Anti Retroviral Therapy).

Mechanism of action
AZT is a thymidine analogue. AZT works by selectively inhibiting HIVs reverse transcriptase, the enzyme that the virus uses to make a DNA copy of its RNA. Reverse transcription is necessary for production of HIVs double-stranded DNA, which would be subsequently integrated into the genetic material of the infected cell (where it is called a provirus).Cellular enzymes convert AZT into the effective 5-triphosphate form. Studies have shown that the termination of HIVs forming DNA chains is the specific factor in the inhibitory effect.At very high doses, AZTs triphosphate form may also inhibit DNA polymerase used by human cells to undergo cell division, but regardless of dosage AZT has an approximately 100-fold greater affinity for HIVs reverse transcriptase. The selectivity has been suggested to be due to the cells ability to quickly repair its own DNA chain if it is disrupted by AZT during its formation, whereas the HIV virus lacks that ability. Thus AZT inhibits HIV replication without affecting the function of uninfected cells. At sufficiently high dosages, AZT begins to inhibit the cellular DNA polymerase used by mitochondria to replicate, accounting for its potentially toxic but reversible effects on cardiac and skeletal muscles, causing myositis.

Chemistry
Enantiopure AZT crystallizes in the monoclinic space group P21. The primary intermolecular bonding motif is a hydrogen bonded dimeric ring formed from two N-H...O interactions.

History
Initial cancer research
In the 1960s, the theory that most cancers were caused by environmental retroviruses gained clinical support and funding. It had recently become known, due to the work of Nobel laureates Howard Temin and David Baltimore, that nearly all avian cancers were caused by bird retroviruses, but corresponding human retroviruses had not yet been found.
In parallel work, other compounds that successfully blocked the synthesis of nucleic acids had been proven to be both antibacterial, antiviral, and anticancer agents, the leading work being done at the laboratory of Nobel laureates George Hitchings and Gertrude Elion, leading to the development of the antitumor agent 6-mercaptopurine.Jerome Horwitz of the Barbara Ann Karmanos Cancer Institute and Wayne State University School of Medicine first synthesized AZT in 1964 under a US National Institutes of Health (NIH) grant. Development was shelved after it proved biologically inert in mice. In 1974, Wolfram Ostertag of the Max Planck Institute for Experimental Medicine in Göttingen, Germany reported that AZT specifically targeted Friend virus (strain of murine leukemia virus).This report attracted little interest from other researchers as the Friend leukemia virus is a retrovirus, and at the time, there were no known human diseases caused by retroviruses.

HIV/AIDS research
In 1983, researchers at the Institut Pasteur in Paris identified the retrovirus now known as the Human Immunodeficiency Virus (HIV) as the cause of acquired immunodeficiency syndrome (AIDS) in humans. Shortly thereafter, Samuel Broder, Hiroaki Mitsuya, and Robert Yarchoan of the United States National Cancer Institute (NCI) initiated a program to develop therapies for HIV/AIDS. Using a line of CD4+ T cells that they had made, they developed an assay to screen drugs for their ability to protect CD4+ T cells from being killed by HIV. In order to expedite the process of discovering a drug, the NCI researchers actively sought collaborations with pharmaceutical companies having access to libraries of compounds with potential antiviral activity. This assay could simultaneously test both the anti-HIV effect of the compounds and their toxicity against infected T cells.
In June 1984, Burroughs-Wellcome virologist Marty St. Clair set up a program to discover drugs with the potential to inhibit HIV replication. Burroughs-Wellcome had expertise in nucleoside analogs and viral diseases, led by researchers including George Hitchings, Gertrude Elion, David Barry, Paul (Chip) McGuirt Jr., Philip Furman, Martha St. Clair, Janet Rideout, Sandra Lehrman and others. Their research efforts were focused in part on the viral enzyme reverse transcriptase. Reverse transcriptase is an enzyme that retroviruses, including HIV, utilize to replicate themselves. Secondary testing was performed in mouse cells infected with the retroviruses Friend virus or Harvey sarcoma virus, as the Wellcome group did not have a viable in-house HIV antiviral assay in place at that time, and these other retroviruses were believed to represent reasonable surrogates. AZT proved to be a remarkably potent inhibitor of both Friend virus and Harvey sarcoma virus, and a search of the companys records showed that it had demonstrated low toxicity when tested for its antibacterial activity in rats many years earlier. Based in part on these results, AZT was selected by nucleoside chemist Janet Rideout as one of 11 compounds to send to the NCI for testing in that organizations HIV antiviral assay.In February 1985, the NCI scientists found that AZT had potent efficacy in vitro.
Several months later, a phase 1 clinical trial of AZT at the NCI was initiated at the NCI and Duke University,.
In doing this Phase I trial, they built on their experience in doing an earlier trial, with suramin, another drug that had shown effective anti-HIV activity in the laboratory. This initial trial of AZT proved that the drug could be safely administered to patients with HIV, that it increased their CD4 counts, restored T cell immunity as measured by skin testing, and that it showed strong evidence of clinical effectiveness, such as inducing weight gain in AIDS patients. It also showed that levels of AZT that worked in vitro could be injected into patients in serum and suppository form, and that the drug penetrated deeply only into infected brains.

Patent filed and FDA approval
A rigorous double-blind, placebo-controlled randomized trial of AZT was subsequently conducted by Burroughs-Wellcome and proved that AZT safely prolongs the lives of people with HIV. Burroughs-Wellcome filed for a patent for AZT in 1985. The Anti-Infective Advisory Committee to United States Food and Drug Administration (FDA) voted ten to one to recommend the approval of AZT. The FDA approved the drug (via the then-new FDA accelerated approval system) for use against HIV, AIDS, and AIDS Related Complex (ARC, a now-obsolete medical term for pre-AIDS illness) on March 20, 1987. The time between the first demonstration that AZT was active against HIV in the laboratory and its approval was 25 months, the shortest period of drug development in recent history.AZT was subsequently approved unanimously for infants and children in 1990. AZT was initially administered in significantly higher dosages than today, typically 400 mg every four hours, day and night, compared to modern dosage of 300 mg twice daily. The paucity of alternatives for treating HIV/AIDS at that time unambiguously affirmed the health risk/benefit ratio, with inevitable slow, disfiguring, and painful death from HIV outweighing the drugs side-effect of transient anemia and malaise.

Society and culture
In 1991, the advocacy group Public Citizen filed a lawsuit claiming that the patents were invalid. Subsequently, Barr Laboratories and Novopharm Ltd. also challenged the patent, in part based on the assertion that NCI scientists Samuel Broder, Hiroaki Mitsuya, and Robert Yarchoan should have been named as inventors, and those two companies applied to the FDA to sell AZT as a generic drug. In response, Burroughs Wellcome Co </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Calaspargase pegol and can you explain it in depth? [/INST] Calaspargase pegol, sold under the brand name Asparlas, is a medication for the treatment of acute lymphoblastic leukemia (ALL).  It is approved in the United States as a component of a multi-agent chemotherapeutic regimen for ALL in pediatric and young adult patients aged one month to 21 years.Calaspargase pegol is an engineered protein consisting of the E. coli-derived enzyme L-asparaginase II conjugated with succinimidyl carbonate monomethoxypolyethylene glycol (pegol). The L-asparaginase portion hydrolyzes L-asparagine to L-aspartic acid depriving the tumor cell of the L-asparagine it needs for survival.  The conjugation with the pegol group increases the half-life of the drug making it longer acting.
The most common (incidence ≥ 10%) grade ≥ 3 adverse reactions are elevated transaminase, increased bilirubin, pancreatitis, and abnormal clotting studies.

History
In December 2018, calaspargase pegol-mknl was approved in the United States as a component of a multi-agent chemotherapeutic regimen for acute lymphoblastic leukemia (ALL) in pediatric and young adult patients age one month to 21 years.Approval was based on a demonstration of the achievement and maintenance of nadir serum asparaginase activity above the level of 0.1 U/mL when using calaspargase pegol-mknl, 2500 U/m2 intravenously, every three weeks. The pharmacokinetics of calaspargase pegol-mknl were studied when administered in combination with multiagent chemotherapy in 124 subjects with B-cell lineage ALL.The FDA approved calaspargase pegol-mknl based on evidence primarily from two clinical trials (Trial 1/NCT01574274 and Trial 2/AALL07P4) of 237 subjects with acute lymphoblastic leukemia (ALL). The trials were conducted in the United States and Canada.Trial 1 enrolled subjects 1 to 20 years old who were recently diagnosed with ALL or lymphoblastic lymphoma. Subjects received calaspargase pegol-mknl or pegaspargase (a drug that helps convert asparagine to other substances) as part of a combination of drugs used for treatment of ALL. The trial had 2 phases. Subjects received calaspargase pegol-mknl or pegaspagase intravenously on Day 7 of the first phase. Subjects received either calaspargase pegol-mknl intravenously every 3 weeks for 10 doses or pegaspargase intravenously every 2 weeks for 15 doses during the second phase. The benefit of calaspargase pegol-mknl was assessed by measuring the activity level of asparginase in the blood on Days 7, 11, 18, 25, and 32 of the first phase and comparing it to pegaspargase.Trial 2 enrolled subjects 1 to 18 years old who were recently diagnosed with high-risk ALL. Subjects received one of 2 doses of calaspargase pegol-mknl or pegaspargase intravenously as part of a combination of drugs used for treatment. Subjects received calaspargase pegol-mknl or pegaspargase on Day 4 of the first phase and Days 2 and 22 of the second phase. Subjects received up to 12 doses of calaspargase pegol-mknl or pegaspargase intravenously depending on the bone marrow response </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Famciclovir and can you explain it in depth? [/INST]  </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Amlodipine and can you explain it in depth? [/INST] Amlodipine, sold under the brand name Norvasc among others, is a calcium channel blocker medication used to treat high blood pressure and coronary artery disease. It is taken by mouth.Common side effects include swelling, feeling tired, abdominal pain, and nausea. Serious side effects may include low blood pressure or heart attack. Whether use is safe during pregnancy or breastfeeding is unclear. When used by people with liver problems, and in elderly individuals, doses should be reduced. Amlodipine works partly by increasing the size of arteries. It is a long-acting calcium channel blocker of the dihydropyridine type.Amlodipine was patented in 1982, and approved for medical use in 1990. It is on the World Health Organizations List of Essential Medicines. It is available as a generic medication. In 2020, it was the fifth most commonly prescribed medication in the United States, with more than 69 million prescriptions.

Medical uses
Amlodipine is used in the management of hypertension and coronary artery disease in people with either stable angina (where chest pain occurs mostly after physical or emotional stress) or vasospastic angina (where it occurs in cycles) and without heart failure. It can be used as either monotherapy or combination therapy for the management of hypertension or coronary artery disease. Amlodipine can be administered to adults and children 6–17 years of age. Calcium channel blockers, including amlodipine, may provide greater protection against stroke than other classes of blood pressure-lowering medications.Amlodipine along with other calcium channel blockers are considered the first choice in the pharmacological management of Raynauds phenomenon.

Combination therapy
Amlodipine can be given as a combination therapy with a variety of medications:
Amlodipine/atorvastatin, where amlodipine is given for hypertension or CAD and atorvastatin prevents cardiovascular events, or if the person also has high cholesterol.
Amlodipine/aliskiren or amlodipine/aliskiren/hydrochlorothiazide if amlodipine alone cannot reduce blood pressure. Aliskiren is a renin inhibitor, which works to reduce primary hypertension (that with no known cause) by binding to renin and preventing it from initiating the renin–angiotensin system (RAAS) pathway to increase blood pressure. Hydrochlorothiazide is a diuretic and decreases overall blood volume.
Amlodipine/benazepril if either drug has failed individually, or amlodipine alone caused edema. Benazepril is an ACE inhibitor and blocks the conversion of angiotensin I to angiotensin II in the RAAS pathway.
Amlodipine/celecoxib
Amlodipine/lisinopril
Amlodipine/olmesartan or amlodipine/olmesartan/hydrochlorothiazide if amlodipine is insufficient in reducing blood pressure. Olmesartan is an angiotensin II receptor antagonist and blocks part of the RAAS pathway.
Amlodipine/perindopril if using amlodipine alone caused edema. Perindopril is a long-lasting ACE inhibitor.
Amlodipine/telmisartan, where telmisartan is an angiotensin II receptor antagonist.
Amlodipine/valsartan or amlodipine/valsartan/hydrochlorothiazide, where valsartan is an angiotensin II receptor antagonist.

Contraindications
The only absolute contraindication to amlodipine is an allergy to amlodipine or any other dihydropyridines.Other situations occur, however, where amlodipine generally should not be used. In patients with cardiogenic shock, where the hearts ventricles are not able to pump enough blood, calcium channel blockers exacerbate the situation by preventing the flow of calcium ions into cardiac cells, which is required for the heart to pump. While use in patients with aortic stenosis (narrowing of the aorta where it meets the left ventricle) since it does not inhibit the ventricles function is generally safe, it can still cause collapse in cases of severe stenosis. In unstable angina (excluding variant angina), amlodipine can cause a reflex increase in cardiac contractility (how hard the ventricles squeeze) and heart rate, which together increase the demand for oxygen by the heart itself. Patients with severe hypotension can have their low blood pressure exacerbated, and patients in heart failure can get pulmonary edema. Those with impaired liver function are unable to metabolize amlodipine to its full extent, giving it a longer half-life than typical.Amlodipines safety in pregnancy has not been established, although reproductive toxicity at high doses is known. Whether amlodipine enters the milk of breastfeeding mothers is also unknown.Those who have heart failure, or recently had a heart attack, should take amlodipine with caution.

Adverse effects
Some common dose-dependent adverse effects of amlodipine include vasodilatory effects, peripheral edema, dizziness, palpitations, and flushing. Peripheral edema (fluid accumulation in the tissues) occurs at rate of 10.8% at a 10-mg dose (versus 0.6% for placebos), and is three times more likely in women than in men. It causes more dilation in the arterioles and precapillary vessels than the postcapillary vessels and venules. The increased dilation allows for more blood, which is unable to push through to the relatively constricted postcapillary venules and vessels; the pressure causes much of the plasma to move into the interstitial space. Amlodipine-association edema can be avoided by adding ACE inhibitors or angiotensin II receptor antagonist. Of the other dose-dependent side effects, palpitations (4.5% at 10 mg vs. 0.6% in placebos) and flushing (2.6% vs. 0%) occurred more often in women; dizziness (3.4% vs. 1.5%) had no sex bias.Common but not dose-related adverse effects are fatigue (4.5% vs. 2.8% with a placebo), nausea (2.9% vs. 1.9%), abdominal pain (1.6% vs. 0.3%), and drowsiness (1.4% vs. 0.6%). Side effects occurring less than 1% of the time include: blood disorders, impotence, depression, peripheral neuropathy, insomnia, tachycardia, gingival enlargement, hepatitis, and jaundice.Amlodipine-associated gingival overgrowth is a relatively common side effect with exposure to amlodipine. Poor dental health and buildup of dental plaque are risk factors.Amlodipine may increase the risk of worsening angina or acute myocardium infarction, especially in those with severe obstructive coronary artery disease, upon dosage initiation or increase. However, depending on the situation, Amlodipine inhibits constriction and restores blood flow in coronary arteries as a result of its property that works directly on vascular smooth muscle causing reduction in peripheral vascular resistance and consequent reduction in blood pressure.

Overdose
Although rare, amlodipine overdose toxicity can result in widening of blood vessels, severe low blood pressure, and fast heart rate. Toxicity is generally managed with fluid replacement monitoring ECG results, vital signs, respiratory system function, glucose levels, kidney function, electrolyte levels, and urine output. Vasopressors are also administered when low blood pressure is not alleviated by fluid resuscitation.

Interactions
Several drugs interact with amlodipine to increase its levels in the body. CYP3A inhibitors, by nature of inhibiting the enzyme that metabolizes amlodipine, CYP3A4, are one such class of drugs. Others include the calcium-channel blocker diltiazem, the antibiotic clarithromycin, and possibly some antifungals. Amlodipine causes several drugs to increase in levels, including cyclosporine, simvastatin, and tacrolimus (the increase in the last one being more likely in people with CYP3A5*3 genetic polymorphisms). When more than 20 mg of simvastatin, a lipid-lowering agent, are given with amlodipine, the risk of myopathy increases. Giving amlodipine with Viagra increases the risk of hypotension.

Pharmacology
Amlodipine is a long-acting calcium channel antagonist that selectively inhibits calcium ion influx across cell membranes. It targets L-type calcium channels in muscle cells and N-type calcium channels in the central nervous system which are involved in nociceptive signalling and pain perception. Amlodipine has an inhibitory effect on calcium influx in smooth muscle cells to inhibit contraction.
Amlodipine ends up significantly reducing total vascular resistance without decreasing cardiac output expressed by pressure-rate product and cardiac contractability in comparison with verapamil, a non-dihydropyridine. In turn, following treatment lasting a month, with amlodipine, cardiac output is significantly enhanced. Unlike verapamil which has efficacy in moderation of emotional arousal and reduces cardiac load without lowering cardiac output demands, amlodipine increases the cardiac output response concomitantly with increased functional cardiac load.

Mechanism of action
Amlodipine is an angioselective calcium channel blocker and inhibits the movement of calcium ions into vascular smooth muscle cells and cardiac muscle cells which inhibits the contraction of cardiac muscle and vascular smooth muscle cells. Amlodipine inhibits calcium ion influx across cell membranes, with a greater effect on vascular smooth muscle cells. This causes vasodilation and a reduction in peripheral vascular resistance, thus lowering blood pressure. Its effects on cardiac muscle also prevent excessive constriction in the coronary arteries.Negative inotropic effects can be detected in vitro, but such effects have not been seen in intact animals at therapeutic doses. Among the two stereoisomers [R(+), S(–)], the (–) isomer has been reported to be more active than the (+) isomer. Serum calcium concentration is not affected by amlodipine. And it specifically inhibits the currents of L-type Cav1.3 channels in the zona glomerulosa of the adrenal gland.The mechanisms by which amlodipine relieves angina are:

Stable angina: amlodipine reduces the total peripheral resistance (afterload) against which the heart works and reduces the rate pressure product, thereby lowering myocardial oxygen demand, at any given level of exercise.
Variant angina: amlodipine blocks spasm of the coronary arteries and restores blood flow in coronary arteries and arterioles in response to calcium, potassium, epinephrine, serotonin, and thromboxane A2 analog in experimental animal models and in human coronary vessels in vitro.Amlodipine has additionally been found to act as an antagonist of the mineralocorticoid receptor, or as an antimineralocorticoid.

Pharmacokinetics
Amlodipine has been studied in healthy volunteers following oral administration of 14C-labelled drug. Amlodipine is well absorbed by the oral route with a mean oral bioavailability around 60%; the half-life of amlodipine is about 30 h to 50 h, and steady-state plasma concentrations are achieved after 7 to 8 days of daily dosing. In the blood it has high plasma protein binding of 97.5%. Its long half-life and high bioavailability are largely in part of its high pKa (8.6); it is ionized at physiological pH, and thus can strongly attract proteins. It is slowly metabolized in the liver by CYP3A4, with its amine group being oxidized and its side ester chain being hydrolyzed, resulting in an inactive pyridine metabolite. Renal elimination is the major route of excretion with about 60% of an administered dose recovered in urine, largely as inactive pyridine metabolites. However, renal impairment does not significantly influence amlodipine elimination. 20-25% of the drug is excreted in the faeces.

History
Pfizers patent protection on Norvasc lasted until 2007; total patent expiration occurred later in 2007. A number of generic versions are available. In the United Kingdom, tablets of amlodipine from different suppliers may contain different salts. The strength of the tablets is expressed in terms of amlodipine base, i.e., without the salts. Tablets containing different salts are therefore considered interchangeable. Fixed-dose combination of amlodipine and perindopril, an angiotensin converting enzyme inhibitor are also available.The medical form comes as besylate, mesylate or maleate.

Veterinary use
Amlodipine is most often used to treat systemic hypertension in cats and dogs. In cats, it is the first line of treatment due to its efficacy and few side effects </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Imipramine and can you explain it in depth? [/INST] Imipramine, sold under the brand name Tofranil, among others, is a tricyclic antidepressant (TCA) mainly used in the treatment of depression. It is also effective in treating anxiety and panic disorder. The drug is also used to treat bedwetting. Imipramine is taken by mouth.
Common side effects of imipramine include dry mouth, drowsiness, dizziness, low blood pressure, rapid heart rate, urinary retention, and electrocardiogram changes. Overdose of the medication can result in death. Imipramine appears to work by increasing levels of serotonin and norepinephrine and by blocking certain serotonin, adrenergic, histamine, and cholinergic receptors.
Imipramine was discovered in 1951 and was introduced for medical use in 1957. It was the first TCA to be marketed. Imipramine and the other TCAs have decreased in use in recent decades, due to the introduction of the selective serotonin reuptake inhibitors (SSRIs), which have fewer side effects and are far safer in overdose.

Medical uses
Imipramine is used in the treatment of depression and certain anxiety disorders. It is similar in efficacy to the antidepressant drug moclobemide. It has also been used to treat nocturnal enuresis because of its ability to shorten the time of delta wave stage sleep, where wetting occurs. In veterinary medicine, imipramine is used with xylazine to induce pharmacologic ejaculation in stallions. Blood levels between 150 and 250 ng/mL of imipramine plus its metabolite desipramine generally correspond to antidepressant efficacy.

Available forms
Imipramine is available in the form of oral tablets and capsules.

Contraindications
Combining it with alcohol consumption causes excessive drowsiness. It may be unsafe during pregnancy.

Side effects
Those listed in italics below denote common side effects.
Central nervous system: dizziness, drowsiness, confusion, seizures, headache, anxiety, tremors, stimulation, weakness, insomnia, nightmares, extrapyramidal symptoms in geriatric patients, increased psychiatric symptoms, paresthesia
Cardiovascular: orthostatic hypotension, ECG changes, tachycardia, hypertension, palpitations, dysrhythmias
Eyes, ears, nose and throat: blurred vision, tinnitus, mydriasis
Gastrointestinal: dry mouth, nausea, vomiting, paralytic ileus, increased appetite, cramps, epigastric distress, jaundice, hepatitis, stomatitis, constipation, taste change
Genitourinary: urinary retention
Hematological: agranulocytosis, thrombocytopenia, eosinophilia, leukopenia
Skin: rash, urticaria, diaphoresis, pruritus, photosensitivity

Overdose
Interactions
Pharmacology
Pharmacodynamics
Imipramine affects numerous neurotransmitter systems known to be involved in the etiology of depression, anxiety, attention-deficit hyperactivity disorder (ADHD), enuresis and numerous other mental and physical conditions. Imipramine is similar in structure to some muscle relaxants, and has a significant analgesic effect and, thus, is very useful in some pain conditions.
The mechanisms of imipramines actions include, but are not limited to, effects on:

Serotonin: very strong reuptake inhibition.
Norepinephrine: strong reuptake inhibition. Desipramine has more affinity to norepinephrine transporter than imipramine.
Dopamine: imipramine blocks D2 receptors. Imipramine, and its metabolite desipramine, have no appreciable affinity for the dopamine transporter (Ki = 8,500 and >10,000 nM, respectively).
Acetylcholine: imipramine is an anticholinergic, specifically an antagonist of the muscarinic acetylcholine receptors. Thus, it is prescribed with caution to the elderly and with extreme caution to those with psychosis, as the general brain activity enhancement in combination with the "dementing" effects of anticholinergics increases the potential of imipramine to cause hallucinations, confusion and delirium in this population.
Epinephrine: imipramine antagonizes adrenergic receptors, thus sometimes causing orthostatic hypotension.
Sigma receptor: activity on sigma receptors is present, but it is very weak (Ki = 520 nM) and it is about half that of amitriptyline (Ki = 300 nM).
Histamine: imipramine is an antagonist of the histamine H1 receptors.
BDNF: BDNF is implicated in neurogenesis in the hippocampus, and studies suggest that depressed patients have decreased levels of BDNF and reduced hippocampal neurogenesis. It is not clear how neurogenesis restores mood, as ablation of hippocampal neurogenesis in murine models do not show anxiety related or depression related behaviours. Chronic imipramine administration results in increased histone acetylation (which is associated with transcriptional activation and decondensed chromatin) at the hippocampal BDNF promoter, and also reduced expression of hippocampal HDAC5.

Pharmacokinetics
Within the body, imipramine is converted into desipramine (desmethylimipramine) as a metabolite.

Chemistry
Imipramine is a tricyclic compound, specifically a dibenzazepine, and possesses three rings fused together with a side chain attached in its chemical structure. Other dibenzazepine TCAs include desipramine (N-desmethylimipramine), clomipramine (3-chloroimipramine), trimipramine (2′-methylimipramine or β-methylimipramine), and lofepramine (N-(4-chlorobenzoylmethyl)desipramine). Imipramine is a tertiary amine TCA, with its side chain-demethylated metabolite desipramine being a secondary amine. Other tertiary amine TCAs include amitriptyline, clomipramine, dosulepin (dothiepin), doxepin, and trimipramine. The chemical name of imipramine is 3-(10,11-dihydro-5H-dibenzo[b,f]azepin-5-yl)-N,N-dimethylpropan-1-amine and its free base form has a chemical formula of C19H24N2 with a molecular weight of 280.407 g/mol. The drug is used commercially mostly as the hydrochloride salt; the embonate (pamoate) salt is used for intramuscular administration and the free base form is not used. The CAS Registry Number of the free base is 50-49-7, of the hydrochloride is 113-52-0, and of the embonate is 10075-24-8.

History
The parent compound of imipramine, 10,11-dihydro-5H-dibenz[b,f]azepine (dibenzazepine), was first synthesized in 1899, but no pharmacological assessment of this compound or any substituted derivatives was undertaken until the late 1940s. Imipramine was first synthesized in 1951, as an antihistamine. The antipsychotic effects of chlorpromazine were discovered in 1952, and imipramine was then developed and studied as an antipsychotic for use in patients with schizophrenia. The medication was tested in several hundred patients with psychosis, but showed little effectiveness. However, imipramine was serendipitously found to possess antidepressant effects in the mid-1950s following a case report of symptom improvement in a woman with severe depression who had been treated with it. This was followed by similar observations in other patients and further clinical research. Subsequently, imipramine was introduced for the treatment of depression in Europe in 1958 and in the United States in 1959. Along with the discovery and introduction of the monoamine oxidase inhibitor iproniazid as an antidepressant around the same time, imipramine resulted in the establishment of monoaminergic drugs as antidepressants.In the late 1950s, imipramine was the first TCA to be developed (by Ciba). At the first international congress of neuropharmacology in Rome, September 1958 Dr Freyhan from the University of Pennsylvania discussed as one of the first clinicians the effects of imipramine in a group of 46 patients, most of them diagnosed as "depressive psychosis". The patients were selected for this study based on symptoms such as depressive apathy, kinetic retardation and feelings of hopelessness and despair. In 30% of all patients, he reported optimal results, and in around 20%, failure. The side effects noted were atropine-like, and most patients experienced dizziness. Imipramine was first tried for treating psychotic disorders such as schizophrenia, but proved ineffective. As an antidepressant, it did well in clinical studies and it is known to work well in even the most severe cases of depression. It is not surprising, therefore, that imipramine may cause a high rate of manic and hypomanic reactions in hospitalized patients with pre-existing bipolar disorder, with one study showing that up to 25% of such patients maintained on Imipramine switched into mania or hypomania. Such powerful antidepressant properties have made it favorable in the treatment of treatment-resistant depression.
Before the advent of selective serotonin reuptake inhibitors (SSRIs), its sometimes intolerable side-effect profile was considered more tolerable. Therefore, it became extensively used as a standard antidepressant and later served as a prototypical drug for the development of the later-released TCAs. Since the 1990s, it has no longer been used as commonly, but is sometimes still prescribed as a second-line treatment for treating major depression . It has also seen limited use in the treatment of migraines, ADHD, and post-concussive syndrome. Imipramine has additional indications for the treatment of panic attacks, chronic pain, and Kleine-Levin syndrome. In pediatric patients, it is relatively frequently used to treat pavor nocturnus and nocturnal enuresis.

Society and culture
Generic names
Imipramine is the English and French generic name of the drug and its INN, BAN, and DCF, while imipramine hydrochloride is its USAN, USP, BANM, and JAN. Its generic name in Spanish and Italian and its DCIT are imipramina, in German is imipramin, and in Latin is imipraminum. The embonate salt is known as imipramine pamoate.

Brand names
Imipramine is marketed throughout the world mainly under the brand name Tofranil. Imipramine pamoate is marketed under the brand name Tofranil-PM for intramuscular injection.

Availability
Imipramine is available for medical use widely throughout the world, including in the United States, the United Kingdom, elsewhere in Europe, India, Brazil, South Africa, Australia, and New Zealand.

References
Further reading
Dean L (2017). "Imipramine Therapy and CYP2D6 and CYP2C19 Genotype".  In Pratt VM, McLeod HL, Rubinstein WS,  et al. (eds.) </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Amfepramone and can you explain it in depth? [/INST] Amfepramone, also known as diethylpropion, is a stimulant drug of the phenethylamine, amphetamine, and cathinone classes that is used as an appetite suppressant </s>


<s> [INST] <<SYS>> You are a responsible assistant committed to providing accurate and helpful responses. Avoid sharing harmful or biased content. Clarify any unclear or incorrect questions rather than providing false or misleading information. <</SYS>> What is Ponesimod and can you explain it in depth? [/INST] Ponesimod, sold under the brand name Ponvory, is a medication for the treatment of multiple sclerosis (MS).The most common side effects include upper respiratory tract infection, hepatic transaminase elevation, and hypertension.Ponesimod was approved for medical use in the United States in March 2021 and in the European Union in June 2021.

Clinical trials
In a 2009–2011 Phase II clinical trial including 464 MS patients, ponesimod treatment resulted in fewer new active brain lesions than placebo, measured during the course of 24 weeks.In a 2010–2012 Phase II clinical trial including 326 patients with psoriasis, 46 or 48% of patients (depending on dosage) had a reduction of at least 75% Psoriasis Area and Severity Index (PASI) score compared to placebo in 16 weeks </s>