<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 Ibuprofen and can you explain it in depth? [/INST] Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used for treating pain, fever, and inflammation. This includes painful menstrual periods, migraines, and rheumatoid arthritis. It may also be used to close a patent ductus arteriosus in a premature baby. It can be used by mouth or intravenously. It typically begins working within an hour.Common side effects include heartburn and a rash. Compared to other NSAIDs, it may have other side effects such as gastrointestinal bleeding. It increases the risk of heart failure, kidney failure, and liver failure. At low doses, it does not appear to increase the risk of heart attack; however, at higher doses it may. Ibuprofen can also worsen asthma. While it is unclear whether it is safe in early pregnancy, it appears to be harmful in later pregnancy and therefore is not recommended. Like other NSAIDs, it works by inhibiting the production of prostaglandins by decreasing the activity of the enzyme cyclooxygenase (COX). Ibuprofen is a weaker anti-inflammatory agent than other NSAIDs.Ibuprofen was discovered in 1961 by Stewart Adams and John Nicholson while working at Boots UK Limited and initially marketed as Brufen. It is available under a number of trade names, including Nurofen, Advil and Motrin. Ibuprofen was first marketed in 1969 in the United Kingdom and in 1974 in the United States. It is on the World Health Organizations List of Essential Medicines. It is available as a generic medication. In 2020, it was the 38th most commonly prescribed medication in the United States, with more than 16 million prescriptions.

Medical uses
Ibuprofen is used primarily to treat fever (including post-vaccination fever), mild to moderate pain (including pain relief after surgery), painful menstruation, osteoarthritis, dental pain, headaches, and pain from kidney stones. About 60% of people respond to any nonsteroidal anti-inflammatory drug; those who do not respond well to a particular one may respond to another.It is used for inflammatory diseases such as juvenile idiopathic arthritis and rheumatoid arthritis. It is also used for pericarditis and patent ductus arteriosus.If a patient is self-treating with over-the-counter Ibuprofen, it should not be taken for more than 10 days, unless the patient has spoken with their doctor.

Lysine
In some countries, ibuprofen lysine (the lysine salt of ibuprofen, sometimes called "ibuprofen lysinate") is licensed for treatment of the same conditions as ibuprofen; the lysine salt is used because it is more water-soluble.Ibuprofen lysine is sold for rapid pain relief; given in form of a lysine salt, absorption is much quicker (35 minutes compared to 90–120 minutes). However, a clinical trial with 351 participants in 2020, funded by Sanofi, found no significant difference between ibuprofen and ibuprofen lysine concerning the eventual onset of action or analgesic efficacy.In 2006, ibuprofen lysine was approved in the U.S. by the Food and Drug Administration (FDA) for closure of patent ductus arteriosus in premature infants weighing between 500 and 1,500 g (1 and 3 lb), who are no more than 32 weeks gestational age when usual medical management (such as fluid restriction, diuretics, and respiratory support) is not effective.

Adverse effects
Adverse effects include nausea, dyspepsia, diarrhea, constipation, gastrointestinal ulceration/bleeding, headache, dizziness, rash, salt and fluid retention, and high blood pressure.Infrequent adverse effects include esophageal ulceration, heart failure, high blood levels of potassium, kidney impairment, confusion, and bronchospasm. Ibuprofen can exacerbate asthma, sometimes fatally.Allergic reactions, including anaphylaxis and anaphylactic shock, may occur. Ibuprofen may be quantified in blood, plasma, or serum to demonstrate the presence of the drug in a person having experienced an anaphylactic reaction, confirm a diagnosis of poisoning in people who are hospitalized, or assist in a medicolegal death investigation. A monograph relating ibuprofen plasma concentration, time since ingestion, and risk of developing renal toxicity in people who have overdosed has been published.In October 2020, the U.S. Food and Drug Administration (FDA) required the drug label to be updated for all nonsteroidal anti-inflammatory medications to describe the risk of kidney problems in unborn babies that result in low amniotic fluid. They recommend avoiding NSAIDs in pregnant women at 20 weeks or later in pregnancy.

Cardiovascular risk
Along with several other NSAIDs, chronic ibuprofen use has been found correlated with risk of progression to hypertension in women, though less than for acetaminophen, and myocardial infarction (heart attack), particularly among those chronically using higher doses. On 9 July 2015, the U.S. Food and Drug Administration (FDA) toughened warnings of increased heart attack and stroke risk associated with ibuprofen and related NSAIDs; the NSAID aspirin is not included in this warning. The European Medicines Agency (EMA) issued similar warnings in 2015.

Skin
Along with other NSAIDs, ibuprofen has been associated with the onset of bullous pemphigoid or pemphigoid-like blistering. As with other NSAIDs, ibuprofen has been reported to be a photosensitising agent, but it is considered a weak photosensitising agent compared to other members of the 2-arylpropionic acid class. Like other NSAIDs, ibuprofen is an extremely rare cause of the autoimmune disease Stevens–Johnson syndrome (SJS). Ibuprofen is also an extremely rare cause of toxic epidermal necrolysis.

Interactions
Alcohol
Drinking alcohol when taking ibuprofen may increase the risk of stomach bleeding.

Aspirin
According to the Food and Drug Administration (FDA), "ibuprofen can interfere with the antiplatelet effect of low-dose aspirin, potentially rendering aspirin less effective when used for cardioprotection and stroke prevention". Allowing sufficient time between doses of ibuprofen and immediate-release (IR) aspirin can avoid this problem. The recommended elapsed time between a dose of ibuprofen and a dose of aspirin depends on which is taken first. It would be 30 minutes or more for ibuprofen taken after IR aspirin, and 8 hours or more for ibuprofen taken before IR aspirin. However, this timing cannot be recommended for enteric-coated aspirin. But, if ibuprofen is taken only occasionally without the recommended timing, the reduction of the cardioprotection and stroke prevention of a daily aspirin regimen is minimal.

Paracetamol
Ibuprofen combined with paracetamol is considered generally safe in children for short-term usage.

Overdose
Ibuprofen overdose has become common since it was licensed for OTC use. Many overdose experiences are reported in the medical literature, although the frequency of life-threatening complications from ibuprofen overdose is low. Human response in cases of overdose ranges from an absence of symptoms to a fatal outcome despite intensive-care treatment. Most symptoms are an excess of the pharmacological action of ibuprofen, and include abdominal pain, nausea, vomiting, drowsiness, dizziness, headache, ear ringing, and nystagmus. Rarely, more severe symptoms, such as gastrointestinal bleeding, seizures, metabolic acidosis, high blood levels of potassium, low blood pressure, slow heart rate, fast heart rate, atrial fibrillation, coma, liver dysfunction, acute kidney failure, cyanosis, respiratory depression, and cardiac arrest have been reported. The severity of symptoms varies with the ingested dose and the time elapsed; however, individual sensitivity also plays an important role. Generally, the symptoms observed with an overdose of ibuprofen are similar to the symptoms caused by overdoses of other NSAIDs.
Correlation between severity of symptoms and measured ibuprofen plasma levels is weak. Toxic effects are unlikely at doses below 100 mg/kg, but can be severe above 400 mg/kg (around 150 tablets of 200 mg units for an average man); however, large doses do not indicate the clinical course is likely to be lethal. A precise lethal dose is difficult to determine, as it may vary with age, weight, and concomitant conditions of the individual person.
Treatment to address an ibuprofen overdose is based on how the symptoms present. In cases presenting early, decontamination of the stomach is recommended. This is achieved using activated charcoal; charcoal adsorbs the drug before it can enter the bloodstream. Gastric lavage is now rarely used, but can be considered if the amount ingested is potentially life-threatening, and it can be performed within 60 minutes of ingestion. Purposeful vomiting is not recommended. The majority of ibuprofen ingestions produce only mild effects, and the management of overdose is straightforward. Standard measures to maintain normal urine output should be instituted and kidney function monitored. Since ibuprofen has acidic properties and is also excreted in the urine, forced alkaline diuresis is theoretically beneficial. However, because ibuprofen is highly protein-bound in the blood, the kidneys excretion of unchanged drug is minimal. Forced alkaline diuresis is, therefore, of limited benefit.

Miscarriage
A Canadian study of pregnant women suggests that those taking any type or amount of NSAIDs (including ibuprofen, diclofenac and naproxen) were 2.4 times more likely to miscarry than those not taking the medications. However, an Israeli study found no increased risk of miscarriage in the group of mothers using NSAIDs.

Pharmacology
NSAIDs such as ibuprofen work by inhibiting the cyclooxygenase (COX) enzymes, which convert arachidonic acid to prostaglandin H2 (PGH2). PGH2, in turn, is converted by other enzymes to several other prostaglandins (which are mediators of pain, inflammation, and fever) and to thromboxane A2 (which stimulates platelet aggregation, leading to the formation of blood clots).
Like aspirin and indomethacin, ibuprofen is a nonselective COX inhibitor, in that it inhibits two isoforms of cyclooxygenase, COX-1 and COX-2. The analgesic, antipyretic, and anti-inflammatory activity of NSAIDs appears to operate mainly through inhibition of COX-2, which decreases the synthesis of prostaglandins involved in mediating inflammation, pain, fever, and swelling. Antipyretic effects may be due to action on the hypothalamus, resulting in an increased peripheral blood flow, vasodilation, and subsequent heat dissipation. Inhibition of COX-1 instead would be responsible for unwanted effects on the gastrointestinal tract. However, the role of the individual COX isoforms in the analgesic, anti-inflammatory, and gastric damage effects of NSAIDs is uncertain, and different compounds cause different degrees of analgesia and gastric damage.Ibuprofen is administered as a racemic mixture. The R-enantiomer undergoes extensive interconversion to the S-enantiomer in vivo. The S-enantiomer is believed to be the more pharmacologically active enantiomer. The R-enantiomer is converted through a series of three main enzymes. These enzymes include acyl-CoA-synthetase, which converts the R-enantiomer to (−)-R-ibuprofen I-CoA; 2-arylpropionyl-CoA epimerase, which converts (−)-R-ibuprofen I-CoA to (+)-S-ibuprofen I-CoA; and hydrolase, which converts (+)-S-ibuprofen I-CoA to the S-enantiomer. In addition to the conversion of ibuprofen to the S-enantiomer, the body can metabolize ibuprofen to several other compounds, including numerous hydroxyl, carboxyl and glucuronyl metabolites. Virtually all of these have no pharmacological effects.Unlike most other NSAIDs, ibuprofen also acts as an inhibitor of Rho kinase and may be useful in recovery from spinal-cord injury.

Pharmacokinetics
After oral administration, peak serum concentration is reached after 1–2 hours, and up to 99% of the drug is bound to plasma proteins. The majority of ibuprofen is metabolized and eliminated within 24 hours in the urine; however, 1% of the unchanged drug is removed through biliary excretion.

Chemistry
Ibuprofen is practically insoluble in water, but very soluble in most organic solvents like ethanol (66.18 g/100 mL at 40 °C for 90% EtOH), methanol, acetone and dichloromethane.The original synthesis of ibuprofen by the Boots Group started with the compound 2-methylpropylbenzene. The synthesis took six steps. A modern, greener technique for the synthesis involves only three steps.

Stereochemistry
Ibuprofen, like other 2-arylpropionate derivatives such as ketoprofen, flurbiprofen and naproxen, contains a stereocenter in the α-position of the propionate moiety.

The product sold in pharmacies is a racemic mixture of the S and R-isomers. The S (dextrorotatory) isomer is the more biologically active; this isomer has been isolated and used medically (see dexibuprofen for details).The isomerase enzyme, alpha-methylacyl-CoA racemase, converts (R)-ibuprofen into the (S)-enantiomer.The (S)- ibuprofen, the eutomer, harbors the desired therapeutic activity. Interestingly, the inactive (R)-enantiomer, the distomer, undergoes a unidirectional chiral inversion to offer the active (S)-enantiomer. That is, when the ibuprofen is administered as a racemate the distomer is converted in vivo into the eutomer while the latter is unaffected.

History
Ibuprofen was derived from propionic acid by the research arm of Boots Group during the 1960s. The name is derived from the 3 functional groups: isobutyl (ibu) propionic acid (pro) phenyl (fen). Its discovery was the result of research during the 1950s and 1960s to find a safer alternative to aspirin. The molecule was discovered and synthesized by a team led by Stewart Adams, with a patent application filed in 1961. Adams initially tested the drug as treatment for his hangover. In 1985, Boots worldwide patent for ibuprofen expired and generic products were launched.The drug was launched as a treatment for rheumatoid arthritis in the United Kingdom in 1969, and in the United States in 1974. Later, in 1983 and 1984, it became the first NSAID (other than aspirin) to be available over the counter (OTC) in these two countries. Boots was awarded the Queens Award for Technical Achievement in 1985 for the development of the drug. Dr. Adams was subsequently awarded an Order of the British Empire (OBE) in 1987.
In November 2013, work on ibuprofen was recognized by the erection of a Royal Society of Chemistry blue plaque at Boots Beeston Factory site in Nottingham, which reads:
In recognition of the work during the 1980s by The Boots Company PLC on the development of ibuprofen which resulted in its move from prescription only status to over the counter sale, therefore expanding its use to millions of people worldwide
and another at BioCity Nottingham, the site of the original laboratory, which reads:
In recognition of the pioneering research work, here on Pennyfoot Street, by Dr Stewart Adams and Dr John Nicholson in the Research Department of Boots which led to the discovery of ibuprofen used by millions worldwide for the relief of pain.

Society and culture
Availability
Ibuprofen was made available under prescription in the United Kingdom in 1969, and in the United States in 1974. In the years since, the good tolerability profile, along with extensive experience in the population, as well as in so-called phase-IV trials (postapproval studies), have resulted in the availability of ibuprofen OTC in pharmacies worldwide, as well as in supermarkets and other general retailers.
Ibuprofen is its International nonproprietary name (INN), British Approved Name (BAN), Australian Approved Name (AAN) and United States Adopted Name (USAN). In the U.S., Motrin has been on the market since 1974, and Advil has been on the market since 1984. Ibuprofen is commonly available in the United States up to the FDAs 1984 dose limit OTC, rarely used higher by prescription.In 2009, the first injectable formulation of ibuprofen was approved in the United States, under the trade name Caldolor.

Route
It can be used by mouth, as a tablet, capsule or suspension, or intravenously.

Research
Ibuprofen is sometimes used for the treatment of acne because of its anti-inflammatory properties, and has been sold in Japan in topical form for adult acne. As with other NSAIDs, ibuprofen may be useful in the treatment of severe orthostatic hypotension (low blood pressure when standing up). NSAIDs are of unclear utility in the prevention and treatment of Alzheimers disease.Ibuprofen has been associated with a lower risk of Parkinsons disease and may delay or prevent it </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 Infliximab and can you explain it in depth? [/INST] Infliximab, a chimeric monoclonal antibody, sold under the brand name Remicade among others, is a medication used to treat a number of autoimmune diseases. This includes Crohns disease, ulcerative colitis, rheumatoid arthritis, ankylosing spondylitis, psoriasis, psoriatic arthritis, and Behçets disease. It is given by slow injection into a vein, typically at six- to eight-week intervals.Common side effects include infections, acute infusion reactions, and abdominal pain. Infliximab is a chimeric monoclonal antibody biologic. It seems to work by binding to and neutralizing TNF-α, preventing it from interacting with its receptors on the cell. TNF-α is a chemical messenger (cytokine) and a key part of the autoimmune reaction.
Infliximab was originally developed in mice as a mouse antibody. Because humans have immune reactions to mouse proteins, the mouse common domains were replaced with similar human antibody domains. They are monoclonal antibodies and have identical structures and affinities to the target. Because they are a combination of mouse and human antibody amino acid sequences, they are called a "chimeric monoclonal antibody".Infliximab was approved for medical use in the United States in 1998, and in the European Union in August 1999. Infliximab biosimilars have been approved in the EU (2013), in Japan (2014), and in the United States (2016, 2017, 2019). It is on the World Health Organizations List of Essential Medicines.

Medical uses
Crohns disease
Three phenotypes, or categories of disease, are present in Crohns disease: stricturing disease (which causes narrowing of the bowel), penetrating disease (which causes fistulae or abnormal connections of the bowel), and inflammatory disease (which primarily causes inflammation).

Fistulizing disease
Infliximab was first used for closure of fistulae in Crohns disease in 1999. In a 94-patient, phase II clinical trial, the researchers showed Infliximab was effective in closing fistulae between the skin and bowel in 56-68% of patients.  A large, 296-patient Phase III clinical trial called the ACCENT 2 trial showed infliximab was additionally beneficial in maintaining closure of fistulae, with almost two-thirds of all patients treated with the three initial doses of infliximab having a fistula response after 14 weeks, and 36% of patients maintaining closure of fistulae after a year, compared with 19% who received placebo therapy.  This final trial resulted in the FDA approval of the drug to treat fistulizing disease.

Inflammatory disease
Infliximab has been used to induce and maintain remission in inflammatory Crohns disease.  The ACCENT 1 trial,  a large, multicentre trial, found 39 to 45% of patients treated with infliximab, who had an initial response to it, maintained remission after 30 weeks, compared with 21% who received placebo treatment.  It also showed a mean maintenance of remission from 38 to 54 weeks compared with 21 weeks for patients who received placebo treatment.Crohns patients have flares of their disease between periods of disease quiescence.  Severe flares are usually treated with steroid medications to obtain remission, but steroids have many undesirable side effects, so some gastroenterologists are now advocating the use of infliximab as the first drug to try to get patients into remission.  This has been called the top-down approach to treatment.

Ulcerative colitis
Infliximab targets TNF, thought to be more related to Th1 cytokines.  Ulcerative colitis was thought to be a Th2 disease, and infliximab would be of limited use.  However, patients with ulcerative colitis have begun to be treated with infliximab on the basis of two large clinical trials conducted in 2005 by Paul Rutgeerts and William Sandborn.  The Acute ulcerative Colitis Treatment trials (ACT1 and ACT2) to evaluate the utility of infliximab in ulcerative colitis showed 44-45% of patients treated with infliximab for a year maintained a response to the medication, compared with 21% of patients who were treated with placebo medication.  At two months, the response was 61-69% for patients treated with infliximab, and 31% for those treated with placebo.Newer drugs such as Etrolizumab have similar efficacy to Infliximab with fewer adverse effects for treatment of ulcerative colitis.

Psoriatic arthritis
In psoriatic arthritis (PsA), inhibitors of TNF, such as infliximab, improve the signs and symptoms. Several therapies with modest efficacy have been studied in nail psoriasis. Among available agents, higher quality data are available to support the efficacy of cyclosporine and infliximab. Based on studies in AS, the results suggest infliximab, etanercept, and adalimumab have the potential to reduce the signs and symptoms of moderate to severely active axial involvement in PsA in patients who have had an inadequate response to NSAID (level 1a, grade A). The anti-TNF agents (infliximab and etanercept; level 1b, grade A) are more effective for the treatment of enthesitis than traditional agents. Results suggest infliximab is effective for the treatment of dactylitis in PsA.

Other
It was approved for treating ankylosing spondylitis, psoriatic arthritis, psoriasis, rheumatoid arthritis.Infliximab is also prescribed (out of indication) for the treatment of Behçets disease.Infliximab is the most frequently used biological agent in treating relapsing polychondritis. Half of the patients saw benefit from this treatment, and a few other patients experienced infections that in some cases lead to death.There have been numerous case reports of the efficacy of infliximab in various inflammatory skin conditions diseases; the FDA approved infliximab for chronic severe plaque psoriasis in adults in September 2006.Infliximab has been used off-label in treating refractory sarcoidosis, where other treatments have not been effective.Infliximab has been tested in chronic obstructive pulmonary disease (COPD) but there was no evidence of benefit with the possibility of harm.Infliximab is indicated for steroid refractory checkpoint inhibitor induced colitis, at a dose of 5 to 10 mg/kg.

Adverse effects
Infliximab has adverse effects, some life-threatening, common to drugs in the class of TNF inhibiting immunosuppressants (which also includes etanercept (Enbrel) and adalimumab (Humira)). Some of the most severe are:

serious infections
reactivation of hepatitis B
reactivation of tuberculosis
lethal hepatosplenic T-cell lymphoma (generally only when combined with 6-mercaptopurine)
drug-induced lupus
demyelinating central nervous system disorders
psoriasis and psoriasiform skin lesions
new-onset vitiligoCases of leukopenia, neutropenia, thrombocytopenia, and pancytopenia (some fatal) have been reported with infliximab. The FDA issued a warning to doctors appearing in the respective product labeling of infliximab instructing them to screen and monitor potential patients more carefully. The FDA issued a warning to doctors that there is an increased risk of lymphoma and other cancers associated with the use of infliximab and other tumor necrosis factor blockers in children and adolescents.Maintenance therapy with the drug (versus intermittent or sporadic therapy) lessens the likelihood of developing antibodies to infliximab which are known to reduce the efficacy of the drug.  Combination treatment with methotrexate (an antifolate drug which suppresses the immune system) has been shown to reduce the formation of these antibodies in patients with rheumatoid arthritis and combination therapy with other immunosuppressants has been shown to reduce the likelihood of these antibodies being formed in Crohns disease.  The use of immunosuppressants may not be necessary in all diseases for which infliximab is indicated, and indiscriminant uses of these other immunosuppressants carry their own risks. Infliximab was studied in monotherapy (without concomitant immunosuppressants such as methotrexate or azathioprine) in psoriasis, psoriatic arthritis, and ankylosing spondylitis. Only its use in rheumatoid arthritis requires the concomitant use of methotrexate by the U.S. Food and Drug Administration (FDA) product labeling; however, the concomitant use of methotrexate in other disease states may help to reduce the bodys immune response to the infliximab and increase its duration of efficacy.

Pharmacology
Infliximab is a purified, recombinant DNA-derived chimeric human-mouse IgG monoclonal antibody that consists of mouse heavy and light chain variable regions combined with human heavy and light chain constant regions. It has a serum half-life of 9.5 days and can be detected in serum 8 weeks after infusion treatment.Infliximab neutralizes the biological activity of TNF-α by binding with high affinity to the soluble (free floating in the blood) and transmembrane (located on the outer membranes of T cells and similar immune cells) forms of TNF-α, and inhibits or prevents the effective binding of TNF-α with its receptors. Infliximab and adalimumab (another TNF antagonist) are in the subclass of "anti-TNF antibodies" (they are in the form of naturally occurring antibodies), and are capable of neutralizing all forms (extracellular-, transmembrane-, and receptor-bound) of TNF-α. Etanercept, a third TNF antagonist, is in a different subclass (receptor-construct fusion protein), and, because of its modified form, cannot neutralize receptor-bound TNF-α. Additionally, the anti-TNF antibodies adalimumab and infliximab have the capability of lysing cells involved in the inflammatory process, whereas the receptor fusion protein apparently lacks this capability. Although the clinical significance of these differences have not been absolutely proven, etanercept, has been shown to perform worse than placebo for Crohns disease. These differences may account for the differential actions of these drugs in both efficacy and side effects.Infliximab has high specificity for TNF-α, and does not neutralize TNF beta (TNFβ, also called lymphotoxin α), an unrelated cytokine that uses different receptors from TNF-α. Biological activities attributed to TNF-α include induction of proinflammatory cytokines (such as interleukins IL-1 and IL-6), enhancement of leukocyte movement or migration from the blood vessels into the tissues (by increasing the permeability of endothelial layer of blood vessels), and increasing the release of adhesion molecules. Infliximab prevents disease in transgenic mice (a special type of mice biologically engineered to produce a human form of TNF-α and which are used to test the results of these drugs that might be expected in humans). These experimental mice develop arthritis as a result of their production of human TNF-α, and when administered after disease onset, infliximab allows eroded joints to heal.Other monoclonal antibodies targeting TNF-α are golimumab, adalimumab, and certolizumab pegol. Etanercept also binds and inhibits the action of TNF-α, but is not a monoclonal antibody (it is instead a fusion of TNF-receptor and an antibody constant region).

History
The importance of TNF in the development of rheumatoid arthritis was originally demonstrated by George Kollias and colleagues in proof of principle studies in transgenic animal models.Infliximab was developed by Junming Le (b.1940) and Jan Vilček (b.1933) at New York University School of Medicine and in collaboration with Centocor, (now Janssen Biotech, Inc.)

Society and culture
Marketing
Remicade is marketed by Janssen Biotech, Inc. (formerly Centocor Biotech, Inc.) in the United States, Mitsubishi Tanabe Pharma in Japan, Xian Janssen in China, and Schering-Plough (now part of Merck & Co) elsewhere.

Biosimilars
In June 2013, two biosimilar versions (Inflectra and Remsima) were submitted for approval in Europe, by Hospira and Celltrion Healthcare respectively. Both had a positive opinion from European Medicines Agencys (EMA) Committee for Medicinal Products for Human Use (CHMP) for sale in the European Union (EU). Celltrion obtained marketing authorization approval (MAA) from 27 EU countries and 3 EEA (European Economic Area) countries by September 2013. Inflectra was approved for use in the European Union in September 2013, and Remsima was approved for use in the European Union in October 2013.In Japan, Celltrion received marketing authorization for Remsima from Japans Ministry of Health, Labour and Welfare (MHLW) in July 2014.In India, Epirus Biopharmaceuticals obtained approval to produce biosimilar infliximab under the brand name "Infimab" (trail name BOW015).The U.S. Food and Drug Administration (FDA) approved Celltrion/Hospira/Pfizers Inflectra (infliximab-dyyb) in April 2016 </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 Fosdenopterin and can you explain it in depth? [/INST] Fosdenopterin (or cyclic pyranopterin monophosphate, cPMP), sold under the brand name Nulibry, is a medication used to reduce the risk of death due to a rare genetic disease known as molybdenum cofactor deficiency type A.The most common side effects include complications related to the intravenous line, fever, respiratory infections, vomiting, gastroenteritis, and diarrhea.Fosdenopterin was approved for medical use in the United States in February 2021,  It is the first medication approved by the U.S. Food and Drug Administration (FDA) for the treatment of molybdenum cofactor deficiency type A. and in the European Union in September 2022.

Medical uses
Fosdenopterin is indicated to reduce the risk of mortality in people with molybdenum cofactor deficiency  (MoCD) type A.

Mechanism of action
People with molybdenum cofactor deficiency type A cannot produce cyclic pyranopterin monophosphate (cPMP) in their body </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 Mesna and can you explain it in depth? [/INST] Mesna, sold under the brand name Mesnex among others, is a medication used in those taking cyclophosphamide or ifosfamide to decrease the risk of bleeding from the bladder. It is used either by mouth or injection into a vein.Common side effects include headache, vomiting, sleepiness, loss of appetite, cough, rash, and joint pain. Serious side effects include allergic reactions. Use during pregnancy appears to be safe for the baby but this use has not been well studied. Mesna is an organosulfur compound. It works by altering the breakdown products of cyclophosphamide and ifosfamide found in the urine making them less toxic.Mesna was approved for medical use in the United States in 1988. It is on the World Health Organizations List of Essential Medicines.

Medical uses
Chemotherapy adjuvant
Mesna is used therapeutically to reduce the incidence of haemorrhagic cystitis and haematuria when a patient receives ifosfamide or cyclophosphamide for cancer chemotherapy. These two anticancer agents, in vivo, may be converted to urotoxic metabolites, such as acrolein.
Mesna assists to detoxify these metabolites by reaction of its sulfhydryl group with α,β-unsaturated carbonyl containing compounds such as acrolein </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 Acitretin and can you explain it in depth? [/INST] Acitretin (trade names Soriatane and Neotigason) is a second-generation retinoid.  It is taken orally, and is typically used for psoriasis.Acitretin is an oral retinoid used in the treatment of severe resistant psoriasis. Because of the potential for problems and severe side effects it is generally used in only very severe cases of psoriasis that have been unresponsive to other treatments.  It binds to nuclear receptors that regulates gene transcription.  They induce keratinocyte differentiation and reduce epidermal hyperplasia, leading to the slowing of cell reproduction.  Acitretin is readily absorbed and widely distributed after oral administration.  A therapeutic effect occurs after two to four weeks or longer.
Patients who have received the medication are advised against giving blood for at least three years due to the risk of birth defects.

Adverse effects
Acitretin is highly teratogenic and noted for the possibility of severe birth defects. It should not be used by pregnant women or women planning to get pregnant within 3 years following the use of acitretin </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 Ciclesonide 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 Trandolapril/verapamil 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 Diazepam and can you explain it in depth? [/INST] Diazepam, first marketed as Valium, is a medicine of the benzodiazepine family that acts as an anxiolytic. It is commonly used to treat a range of conditions, including anxiety, seizures, alcohol withdrawal syndrome, muscle spasms, insomnia, and restless legs syndrome. It may also be used to cause memory loss during certain medical procedures. It can be taken by mouth, inserted into the rectum, injected into muscle, injected into a vein or used as a nasal spray. When given into a vein, effects begin in one to five minutes and last up to an hour. By mouth, effects begin after 15 to 60 minutes.Common side effects include sleepiness and trouble with coordination. Serious side effects are rare. They include increased risk of suicide, decreased breathing, and an increased risk of seizures if used too frequently in those with epilepsy. Occasionally, excitement or agitation may occur. Long-term use can result in tolerance, dependence, and withdrawal symptoms on dose reduction. Abrupt stopping after long-term use can be potentially dangerous. After stopping, cognitive problems may persist for six months or longer. It is not recommended during pregnancy or breastfeeding. Its mechanism of action works by increasing the effect of the neurotransmitter gamma-aminobutyric acid (GABA).Diazepam was patented in 1959 by Hoffmann-La Roche. It has been one of the most frequently prescribed medications in the world since its launch in 1963. In the United States it was the best-selling medication between 1968 and 1982, selling more than 2 billion tablets in 1978 alone. In 2019, it was the 117th most commonly prescribed medication in the United States, with more than 5 million prescriptions. In 1985 the patent ended, and there are now more than 500 brands available on the market. It is on the World Health Organizations List of Essential Medicines.

Medical uses
Diazepam is mainly used to treat anxiety, insomnia, panic attacks and symptoms of acute alcohol withdrawal. It is also used as a premedication for inducing sedation, anxiolysis, or amnesia before certain medical procedures (e.g., endoscopy). In 2020, it was approved for use in the United States as a nasal spray to interrupt seizure activity in people with epilepsy. Diazepam is the most commonly used benzodiazepine for "tapering" benzodiazepine dependence due to the drugs comparatively long half-life, allowing for more efficient dose reduction. Benzodiazepines have a relatively low toxicity in overdose.Diazepam has a number of uses including:

Treatment of anxiety, panic attacks, and states of agitation
Treatment of neurovegetative symptoms associated with vertigo
Treatment of the symptoms of alcohol, opiate, and benzodiazepine withdrawal
Short-term treatment of insomnia
Treatment of muscle spasms
Treatment of tetanus, together with other measures of intensive treatment
Adjunctive treatment of spastic muscular paresis (paraplegia/tetraplegia) caused by cerebral or spinal cord conditions such as stroke, multiple sclerosis, or spinal cord injury (long-term treatment is coupled with other rehabilitative measures)
Palliative treatment of stiff person syndrome
Pre- or postoperative sedation, anxiolysis or amnesia (e.g., before endoscopic or surgical procedures)
Treatment of complications with stimulant overdoses and psychosis, such as cocaine or methamphetamineUsed in treatment of organophosphate poisoning and reduces the risk of seizure induced brain and cardiac damage.

Preventive treatment of oxygen toxicity during hyperbaric oxygen therapyDosages should be determined on an individual basis, depending on the condition being treated, severity of symptoms, patient body weight, and any other conditions the person may have.

Seizures
Intravenous diazepam or lorazepam are first-line treatments for status epilepticus. However, intravenous lorazepam has advantages over intravenous diazepam, including a higher rate of terminating seizures and a more prolonged anticonvulsant effect. Diazepam gel was better than placebo gel in reducing the risk of non-cessation of seizures. Diazepam is rarely used for the long-term treatment of epilepsy because tolerance to its anticonvulsant effects usually develops within six to 12 months of treatment, effectively rendering it useless for that purpose.The anticonvulsant effects of diazepam can help in the treatment of seizures due to a drug overdose or chemical toxicity as a result of exposure to sarin, VX, or soman (or other organophosphate poisons), lindane, chloroquine, physostigmine, or pyrethroids.Diazepam is sometimes used intermittently for the prevention of febrile seizures that may occur in children under five years of age. Recurrence rates are reduced, but side effects are common so the decision to treat febrile seizures (which are benign in nature) with medication should use this as part of the evaluation. Long-term use of diazepam for the management of epilepsy is not recommended; however, a subgroup of individuals with treatment-resistant epilepsy benefit from long-term benzodiazepines, and for such individuals, clorazepate has been recommended due to its slower onset of tolerance to the anticonvulsant effects.

Alcohol withdrawal
Because of its relatively long duration of action, and evidence of safety and efficacy, diazepam is preferred over other benzodiazepines for treatment of persons experiencing moderate to severe alcohol withdrawal. An exception to this is when a medication is required intramuscular in which case either lorazepam or midazolam is recommended.

Other
Diazepam is used for the emergency treatment of eclampsia, when IV magnesium sulfate and blood-pressure control measures have failed. Benzodiazepines do not have any pain-relieving properties themselves, and are generally recommended to avoid in individuals with pain. However, benzodiazepines such as diazepam can be used for their muscle-relaxant properties to alleviate pain caused by muscle spasms and various dystonias, including blepharospasm. Tolerance often develops to the muscle relaxant effects of benzodiazepines such as diazepam. Baclofen is sometimes used as an alternative to diazepam.

Availability
Diazepam is marketed in over 500 brands throughout the world. It is supplied in oral, injectable, inhalation, and rectal forms.The United States military employs a specialized diazepam preparation known as  Convulsive Antidote, Nerve Agent (CANA), which contains diazepam. One CANA kit is typically issued to service members, along with three Mark I NAAK kits, when operating in circumstances where chemical weapons in the form of nerve agents are considered a potential hazard. Both of these kits deliver drugs using autoinjectors. They are intended for use in "buddy aid" or "self aid" administration of the drugs in the field prior to decontamination and delivery of the patient to definitive medical care.

Contraindications
Use of diazepam should be avoided, when possible, in individuals with:
Ataxia
Severe hypoventilation
Acute narrow-angle glaucoma
Severe hepatic deficiencies (hepatitis and liver cirrhosis decrease elimination by a factor of two)
Severe renal deficiencies (for example, patients on dialysis)
Liver disorders
Severe sleep apnea
Severe depression, particularly when accompanied by suicidal tendencies
Psychosis
Pregnancy or breast feeding
Caution required in elderly or debilitated patients
Coma or shock
Abrupt discontinuation of therapy
Acute intoxication with alcohol, narcotics, or other psychoactive substances (with the exception of hallucinogens or some stimulants, where it is occasionally used as a treatment for overdose)
History of alcohol or drug dependence
Myasthenia gravis, an autoimmune disorder causing marked fatiguability
Hypersensitivity or allergy to any drug in the benzodiazepine class

Caution
Benzodiazepine abuse and misuse should be guarded against when prescribed to those with alcohol or drug dependencies or who have psychiatric disorders.
Pediatric patients
Less than 18 years of age, this treatment is usually not indicated, except for treatment of epilepsy, and pre- or postoperative treatment. The smallest possible effective dose should be used for this group of patients.
Under 6 months of age, safety and effectiveness have not been established; diazepam should not be given to those in this age group.
Elderly and very ill patients can possibly experience apnea or cardiac arrest. Concomitant use of other central nervous system depressants increases this risk. The smallest possible effective dose should be used for this group of people. The elderly metabolise benzodiazepines much more slowly than younger adults, and are also more sensitive to the effects of benzodiazepines, even at similar blood plasma levels. Doses of diazepam are recommended to be about half of those given to younger people, and treatment limited to a maximum of two weeks. Long-acting benzodiazepines such as diazepam are not recommended for the elderly. Diazepam can also be dangerous in geriatric patients owing to a significant increased risk of falls.
Intravenous or intramuscular injections in hypotensive people or those in shock should be administered carefully and vital signs should be monitored.
Benzodiazepines such as diazepam are lipophilic and rapidly penetrate membranes, so rapidly cross over into the placenta with significant uptake of the drug. Use of benzodiazepines including diazepam in late pregnancy, especially high doses, can result in floppy infant syndrome. Diazepam when taken late in pregnancy, during the third trimester, causes a definite risk of a severe benzodiazepine withdrawal syndrome in the neonate with symptoms including hypotonia, and reluctance to suck, to apnoeic spells, cyanosis, and impaired metabolic responses to cold stress. Floppy infant syndrome and sedation in the newborn may also occur. Symptoms of floppy infant syndrome and the neonatal benzodiazepine withdrawal syndrome have been reported to persist from hours to months after birth.

Adverse effects
Adverse effects of benzodiazepines such as diazepam include anterograde amnesia, confusion (especially pronounced in higher doses) and sedation. The elderly are more prone to adverse effects of diazepam, such as confusion, amnesia, ataxia, and hangover effects, as well as falls. Long-term use of benzodiazepines such as diazepam is associated with drug tolerance, benzodiazepine dependence, and benzodiazepine withdrawal syndrome. Like other benzodiazepines, diazepam can impair short-term memory and learning of new information. While benzodiazepine drugs such as diazepam can cause anterograde amnesia, they do not cause retrograde amnesia; information learned before using benzodiazepines is not impaired. Tolerance to the cognitively impairing effects of benzodiazepines does not tend to develop with long-term use, and the elderly are more sensitive to them. Additionally, after cessation of benzodiazepines, cognitive deficits may persist for at least six months; it is unclear whether these impairments take longer than six months to abate or if they are permanent. Benzodiazepines may also cause or worsen depression. Infusions or repeated intravenous injections of diazepam when managing seizures, for example, may lead to drug toxicity, including respiratory depression, sedation and hypotension. Drug tolerance may also develop to infusions of diazepam if it is given for longer than 24 hours. Sedatives and sleeping pills, including diazepam, have been associated with an increased risk of death.In September 2020, the U.S. Food and Drug Administration (FDA) required the boxed warning be updated for all benzodiazepine medicines to describe the risks of abuse, misuse, addiction, physical dependence, and withdrawal reactions consistently across all the medicines in the class.Diazepam has a range of side effects common to most benzodiazepines, including:

Suppression of REM sleep and Slow wave sleep
Impaired motor function
Impaired coordination
Impaired balance
Dizziness
Reflex tachycardiaLess commonly, paradoxical side effects can occur, including nervousness, irritability, excitement, worsening of seizures, insomnia, muscle cramps, changes in libido,  and in some cases, rage and violence. These adverse reactions are more likely to occur in children, the elderly, and individuals with a history of a substance use disorder, such as an alcohol use disorder, or a history of aggressive behavior. In some people, diazepam may increase the propensity toward self-harming behaviours and, in extreme cases, may provoke suicidal tendencies or acts. Very rarely dystonia can occur.Diazepam may impair the ability to drive vehicles or operate machinery. The impairment is worsened by consumption of alcohol, because both act as central nervous system depressants.During the course of therapy, tolerance to the sedative effects usually develops, but not to the anxiolytic and myorelaxant effects.Patients with severe attacks of apnea during sleep may experience respiratory depression (hypoventilation), leading to respiratory arrest and death.Diazepam in doses of 5 mg or more causes significant deterioration in alertness performance combined with increased feelings of sleepiness.

Tolerance and withdrawal
Diazepam, as with other benzodiazepine drugs, can cause tolerance, physical dependence, substance use disorder, and benzodiazepine withdrawal syndrome. Withdrawal from diazepam or other benzodiazepines often leads to withdrawal symptoms similar to those seen during barbiturate or alcohol withdrawal. The higher the dose and the longer the drug is taken, the greater the risk of experiencing unpleasant withdrawal symptoms.Withdrawal symptoms can occur from standard dosages and also after short-term use, and can range from insomnia and anxiety to more serious symptoms, including seizures and psychosis. Withdrawal symptoms can sometimes resemble pre-existing conditions and be misdiagnosed. Diazepam may produce less intense withdrawal symptoms due to its long elimination half-life.Benzodiazepine treatment should be discontinued as soon as possible by a slow and gradual dose reduction regimen. Tolerance develops to the therapeutic effects of benzodiazepines; for example tolerance occurs to the anticonvulsant effects and as a result benzodiazepines are not generally recommended for the long-term management of epilepsy. Dose increases may overcome the effects of tolerance, but tolerance may then develop to the higher dose and adverse effects may increase. The mechanism of tolerance to benzodiazepines includes uncoupling of receptor sites, alterations in gene expression, down-regulation of receptor sites, and desensitisation of receptor sites to the effect of GABA. About one-third of individuals who take benzodiazepines for longer than four weeks become dependent and experience withdrawal syndrome on cessation.Differences in rates of withdrawal (50–100%) vary depending on the patient sample. For example, a random sample of long-term benzodiazepine users typically finds around 50% experience few or no withdrawal symptoms, with the other 50% experiencing notable withdrawal symptoms. Certain select patient groups show a higher rate of notable withdrawal symptoms, up to 100%.Rebound anxiety, more severe than baseline anxiety, is also a common withdrawal symptom when discontinuing diazepam or other benzodiazepines. Diazepam is therefore only recommended for short-term therapy at the lowest possible dose owing to risks of severe withdrawal problems from low doses even after gradual reduction. The risk of pharmacological dependence on diazepam is significant, and patients experience symptoms of benzodiazepine withdrawal syndrome if it is taken for six weeks or longer. In humans, tolerance to the anticonvulsant effects of diazepam occurs frequently.

Dependence
Improper or excessive use of diazepam can lead to dependence. At a particularly high risk for diazepam misuse, substance use disorder or dependence are:

People with a history of a substance use disorder or substance dependence Diazepam increases craving for alcohol in problem alcohol consumers. Diazepam also increases the volume of alcohol consumed by problem drinkers.
People with severe personality disorders, such as borderline personality disorderPatients from the aforementioned groups should be monitored very closely during therapy for signs of abuse and development of dependence. Therapy should be discontinued if any of these signs are noted, although if dependence has developed, therapy must still be discontinued gradually to avoid severe withdrawal symptoms. Long-term therapy in such instances is not recommended.People suspected of being dependent on benzodiazepine drugs should be very gradually tapered off the drug. Withdrawals can be life-threatening, particularly when excessive doses have been taken for extended periods of time. Equal prudence should be used whether dependence has occurred in therapeutic or recreational contexts.Diazepam is a good choice for tapering for those using high doses of other benzodiazepines since it has a long half-life thus withdrawal symptoms are tolerable. The process is very slow (usually from 14 to 28 weeks) but is considered safe when done appropriately.

Overdose
An individual who has consumed too much diazepam typically displays one or more of these symptoms in a period of approximately four hours immediately following a suspected overdose:
Drowsiness
Mental confusion
Hypotension
Impaired motor functions
Impaired reflexes
Impaired coordination
Impaired balance
Dizziness
ComaAlthough not usually fatal when taken alone, a diazepam overdose is considered a medical emergency and generally requires the immediate attention of medical personnel. The antidote for an overdose of diazepam (or any other benzodiazepine) is flumazenil (Anexate). This drug is only used in cases with severe respiratory depression or cardiovascular complications. Because flumazenil is a short-acting drug, and the effects of diazepam can last for days, several doses of flumazenil may be necessary. Artificial respiration and stabilization of cardiovascular functions may also be necessary. Though not routinely indicated, activated charcoal can be used for decontamination of the stomach following a diazepam overdose. Emesis is contraindicated. Dialysis is minimally effective. Hypotension may be treated with levarterenol or metaraminol.The oral LD50 (lethal dose in 50% of the population) of diazepam is 720 mg/kg in mice and 1240 mg/kg in rats. D. J. Greenblatt and colleagues reported in 1978 on two patients who had taken 500 and 2000 mg of diazepam, respectively, went into moderately deep comas, and were discharged within 48 hours without having experienced any important complications, in spite of having high concentrations of diazepam and its metabolites desmethyldiazepam, oxazepam, and temazepam, according to samples taken in the hospital and as follow-up.Overdoses of diazepam with alcohol, opiates or other depressants may be fatal.

Interactions
If diazepam is administered concomitantly with other drugs, attention should be paid to the possible pharmacological interactions. Particular care should be taken with drugs that potentiate the effects of diazepam, such as barbiturates, phenothiazines, opioids, and antidepressants.Diazepam does not increase or decrease hepatic enzyme activity, and does not alter the metabolism of other compounds. No evidence would suggest diazepam alters its own metabolism with chronic administration.Agents with an effect on hepatic cytochrome P450 pathways or conjugation can alter the rate of diazepam metabolism. These interactions would be expected to be most significant with long-term diazepam therapy, and their clinical significance is variable.
Diazepam increases the central depressive effects of alcohol, other hypnotics/sedatives (e.g., barbiturates), other muscle relaxants, certain antidepressants, sedative antihistamines, opioids, and antipsychotics, as well as anticonvulsants such as phenobarbital, phenytoin, and carbamazepine. The euphoriant effects of opioids may be increased, leading to increased risk of psychological dependence.
Cimetidine, omeprazole, oxcarbazepine, ticlopidine, topiramate, ketoconazole, itraconazole, disulfiram, fluvoxamine, isoniazid, erythromycin, probenecid, propranolol, imipramine, ciprofloxacin, fluoxetine, and valproic acid prolong the action of diazepam by inhibiting its elimination.
Alcohol in combination with diazepam may cause a synergistic enhancement of the hypotensive properties of benzodiazepines and alcohol.
Oral contraceptives significantly decrease the elimination of desmethyldiazepam, a major metabolite of diazepam.
Rifampin, phenytoin, carbamazepine, and phenobarbital increase the metabolism of diazepam, thus decreasing drug levels and effects. Dexamethasone and St Johns wort also increase the metabolism of diazepam.
Diazepam increases the serum levels of phenobarbital.
Nefazodone can cause increased blood levels of benzodiazepines.
Cisapride may enhance the absorption, and therefore the sedative activity, of diazepam.
Small doses of theophylline may inhibit the action of diazepam.
Diazepam may block the action of levodopa (used in the treatment of Parkinsons disease).
Diazepam may alter digoxin serum concentrations.
Other drugs that may have interactions with diazepam include antipsychotics (e.g. chlorpromazine), MAO inhibitors, and ranitidine.
Because it acts on the GABA receptor, the herb valerian may produce an adverse effect.
Foods that acidify the urine can lead to faster absorption and elimination of diazepam, reducing drug levels and activity.
Foods that alkalinize the urine can lead to slower absorption and elimination of diazepam, increasing drug levels and activity.
Reports conflict as to whether food in general has any effects on the absorption and activity of orally administered diazepam.

Pharmacology
Diazepam is a long-acting "classical" benzodiazepine. Other classical benzodiazepines include chlordiazepoxide, clonazepam, lorazepam, oxazepam, nitrazepam, temazepam, flurazepam, bromazepam, and clorazepate. Diazepam has anticonvulsant properties. Benzodiazepines act via micromolar benzodiazepine binding sites as calcium channel blockers and significantly inhibit depolarization-sensitive calcium uptake in rat nerve cell preparations.Diazepam inhibits acetylcholine release in mouse hippocampal synaptosomes. This has been found by measuring sodium-dependent high-affinity choline uptake in mouse brain cells in vitro, after pretreatment of the mice with diazepam in vivo. This may play a role in explaining diazepams anticonvulsant properties.Diazepam binds with high affinity to glial cells in animal cell cultures. Diazepam at high doses has been found to decrease histamine turnover in mouse brain via diazepams action at the benzodiazepine-GABA receptor complex. Diazepam also decreases prolactin release in rats.

Mechanism of action
Benzodiazepines are positive allosteric modulators of the GABA type A receptors (GABAA). The GABAA receptors are ligand-gated chloride-selective ion channels that are activated by GABA, the major inhibitory neurotransmitter in the brain. Binding of benzodiazepines to this receptor complex promotes the binding of GABA, which in turn increases the total conduction of chloride ions across the neuronal cell membrane. This increased chloride ion influx hyperpolarizes the neurons membrane potential. As a result, the difference between resting potential and threshold potential is increased and firing is less likely. As a result, the arousal of the cortical and limbic systems in the central nervous system is reduced.The GABAA receptor is a heteromer composed of five subunits, the most common ones being two αs, two βs, and one γ (α2β2γ). For each subunit, many subtypes exist (α1–6, β1–3, and γ1–3). GABAA receptors containing the α1 subunit mediate the sedative, the anterograde amnesic, and partly the anticonvulsive effects of diazepam. GABAA receptors containing α2 mediate the anxiolytic actions and to a large degree the myorelaxant effects. GABAA receptors containing α3 and α5 also contribute to benzodiazepines myorelaxant actions, whereas GABAA receptors comprising the α5 subunit were shown to modulate the temporal and spatial memory effects of benzodiazepines. Diazepam is not the only drug to target these GABAA receptors. Drugs such as flumazenil also bind to GABAA to induce their effects.Diazepam appears to act on areas of the limbic system, thalamus, and hypothalamus, inducing anxiolytic effects. Benzodiazepine drugs including diazepam increase the inhibitory processes in the cerebral cortex.The anticonvulsant properties of diazepam and other benzodiazepines may be in part or entirely due to binding to voltage-dependent sodium channels rather than benzodiazepine receptors. Sustained repetitive firing seems limited by benzodiazepines effect of slowing recovery of sodium channels from inactivation.The muscle relaxant properties of diazepam are produced via inhibition of polysynaptic pathways in the spinal cord.

Pharmacokinetics
Diazepam can be administered orally, intravenously (must be diluted, as it is painful and damaging to veins), intramuscularly (IM), or as a suppository.The onset of action is one to five minutes for IV administration and 15–30 minutes for IM administration. The duration of diazepams peak pharmacological effects is 15 minutes to one hour for both routes of administration. The half-life of diazepam in general is 30–56 hours. Peak plasma levels occur between 30 and 90 minutes after oral administration and between 30 and 60 minutes after intramuscular administration; after rectal administration, peak plasma levels occur after 10 to 45 minutes. Diazepam is highly protein-bound, with 96 to 99% of the absorbed drug being protein-bound. The distribution half-life of diazepam is two to 13 minutes.Diazepam is highly lipid-soluble, and is widely distributed throughout the body after administration. It easily crosses both the blood–brain barrier and the placenta, and is excreted into breast milk. After absorption, diazepam is redistributed into muscle and adipose tissue. Continual daily doses of diazepam quickly build to a high concentration in the body (mainly in adipose tissue), far in excess of the actual dose for any given day.Diazepam is stored preferentially in some organs, including the heart. Absorption by any administered route and the risk of accumulation is significantly increased in the neonate, and withdrawal of diazepam during pregnancy and breast feeding is clinically justified.Diazepam undergoes oxidative metabolism by demethylation (CYP 2C9, 2C19, 2B6, 3A4, and 3A5), hydroxylation (CYP 3A4 and 2C19) and glucuronidation in the liver as part of the cytochrome P450 enzyme system. It has several pharmacologically active metabolites. The main active metabolite of diazepam is desmethyldiazepam (also known as nordazepam or nordiazepam). Its other active metabolites include the minor active metabolites temazepam and oxazepam. These metabolites are conjugated with glucuronide, and are excreted primarily in the urine. Because of these active metabolites, the serum values of diazepam alone are not useful in predicting the effects of the drug. Diazepam has a biphasic half-life of about one to three days, and two to seven days for the active metabolite desmethyldiazepam. Most of the drug is metabolised; very little diazepam is excreted unchanged. The elimination half-life of diazepam and also the active metabolite desmethyldiazepam increases significantly in the elderly, which may result in prolonged action, as well as accumulation of the drug during repeated administration.

Physical and chemical properties
Diazepam is a 1,4-benzodiazepine. Diazepam occurs as solid white or yellow crystals with a melting point of 131.5 to 134.5 °C. It is odorless, and has a slightly bitter taste. The British Pharmacopoeia lists it as being very slightly soluble in water, soluble in alcohol, and freely soluble in chloroform. The United States Pharmacopoeia lists diazepam as soluble 1 in 16 ethyl alcohol, 1 in 2 of chloroform, 1 in 39 ether, and practically insoluble in water. The pH of diazepam is neutral (i.e., pH = 7). Due to additives such as benzoic acid/benzoate in the injectable form. (Plumbs, 6th edition page 372) Diazepam has a shelf life of five years for oral tablets and three years for IV/IM solutions.
Diazepam should be stored at room temperature (15–30 °C). The solution for parenteral injection should be protected from light and kept from freezing. The oral forms should be stored in air-tight containers and protected from light.Diazepam can absorb into plastics, so liquid preparations should not be kept in plastic bottles or syringes, etc. As such, it can leach into the plastic bags and tubing used for intravenous infusions. Absorption appears to depend on several factors, such as temperature, concentration, flow rates, and tube length. Diazepam should not be administered if a precipitate has formed and does not dissolve.

Detection in body fluids
Diazepam may be quantified in blood or plasma to confirm a diagnosis of poisoning in hospitalized patients, provide evidence in an impaired driving arrest, or to assist in a medicolegal death investigation. Blood or plasma diazepam concentrations are usually in a range of 0.1–1.0 mg/L in persons receiving the drug therapeutically. Most commercial immunoassays for the benzodiazepine class of drugs cross-react with diazepam, but confirmation and quantitation are usually performed using chromatographic techniques.

History
Diazepam was the second benzodiazepine invented by Leo Sternbach of Hoffmann-La Roche at the companys Nutley, New Jersey, facility following chlordiazepoxide (Librium), which was approved for use in 1960. Released in 1963 as an improved version of Librium, diazepam became incredibly popular, helping Roche to become a pharmaceutical industry giant. It is 2.5 times more potent than its predecessor, which it quickly surpassed in terms of sales. After this initial success, other pharmaceutical companies began to introduce other benzodiazepine derivatives.The benzodiazepines gained popularity among medical professionals as an improvement over barbiturates, which have a comparatively narrow therapeutic index, and are far more sedative at therapeutic doses. The benzodiazepines are also far less dangerous; death rarely results from diazepam overdose, except in cases where it is consumed with large amounts of other depressants (such as alcohol or opioids). Benzodiazepine drugs such as diazepam initially had widespread public support, but with time the view changed to one of growing criticism and calls for restrictions on their prescription.Marketed by Roche using an advertising campaign conceived by the William Douglas McAdams Agency under the leadership of Arthur Sackler, diazepam was the top-selling pharmaceutical in the United States from 1969 to 1982, with peak annual sales in 1978 of 2.3 billion tablets. Diazepam, along with oxazepam, nitrazepam and temazepam, represents 82% of the benzodiazepine market in Australia. While psychiatrists continue to prescribe diazepam for the short-term relief of anxiety, neurology has taken the lead in prescribing diazepam for the palliative treatment of certain types of epilepsy and spastic activity, for example, forms of paresis. It is also the first line of defense for a rare disorder called stiff-person syndrome.

Society and culture
Recreational use
Diazepam is a medication with a high risk of misuse and can cause drug dependence. Urgent action by national governments has been recommended to improve prescribing patterns of benzodiazepines such as diazepam. A single dose of diazepam modulates the dopamine system in similar ways to how morphine and alcohol modulate the dopaminergic pathways.
Between 50 and 64% of rats will self-administer diazepam.
Diazepam has been shown to be able to substitute for the behavioural effects of barbiturates in a primate study.
Diazepam has been found as an adulterant in heroin.Diazepam drug misuse can occur either through recreational misuse where the drug is taken to achieve a high or when the drug is continued long term against medical advice.Sometimes, it is used by stimulant users to "come down" and sleep and to help control the urge to binge. These users often escalate dosage from 2 to 25 times the therapeutic dose of 5 to 10 mg.A large-scale study in the US, conducted by SAMHSA, using data from 2011, determined benzodiazepines were present in 28.7% of emergency department visits involving nonmedical use of pharmaceuticals. In this regard, benzodiazepines are second only to opiates, the study found in 39.2% of visits. About 29.3% of drug-related suicide attempts involve benzodiazepines, making them the most frequently represented class in drug-related suicide attempts. Males misuse benzodiazepines as commonly as females.Diazepam was detected in 26% of cases of people suspected of driving under the influence of drugs in Sweden, and its active metabolite nordazepam was detected in 28% of cases. Other benzodiazepines and zolpidem and zopiclone also were found in high numbers. Many drivers had blood levels far exceeding the therapeutic dose range, suggesting a high degree of potential for misuse for benzodiazepines, zolpidem, and zopiclone. In Northern Ireland, in cases where drugs were detected in samples from impaired drivers who were not impaired by alcohol, benzodiazepines were found in 87% of cases. Diazepam was the most commonly detected benzodiazepine.

Legal status
Diazepam is regulated in most countries as a prescription drug:

International
Diazepam is a Schedule IV controlled drug under the Convention on Psychotropic Substances.

UK
Classified as a controlled drug, listed under Schedule IV, Part I (CD Benz POM) of the Misuse of Drugs Regulations 2001, allowing possession with a valid prescription. The Misuse of Drugs Act 1971 makes it illegal to possess the drug without a prescription, and for such purposes it is classified as a Class C drug.

Germany
Classified as a prescription drug, or in high dosage as a restricted drug (Betäubungsmittelgesetz, Anlage III).

Australia
Diazepam is Schedule 4 substance under the Poisons Standard (June 2018). A schedule 4 drug is outlined in the Poisons Act 1964 as, "Substances, the use or supply of which should be by or on the order of persons permitted by State or Territory legislation to prescribe and should be available from a pharmacist on prescription."

United States
Diazepam is controlled as a Schedule IV substance under the Controlled Substances Act of 1970.

Judicial executions
The states of California and Florida offer diazepam to condemned inmates as a pre-execution sedative as part of their lethal injection program, although the state of California has not executed a prisoner since 2006. In August 2018, Nebraska used diazepam as part of the drug combination used to execute Carey Dean Moore, the first death row inmate executed in Nebraska in over 21 years.

Veterinary uses
Diazepam is used as a short-term sedative and anxiolytic for cats and dogs, sometimes used as an appetite stimulant. It can also be used to stop seizures in dogs and cats.

References
Further reading
Dean L (2016). "Diazepam Therapy 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 Buprenorphine and can you explain it in depth? [/INST] Buprenorphine is an opioid used to treat opioid use disorder, acute pain, and chronic pain. It can be used under the tongue (sublingual), in the cheek (buccal), by injection (intravenous and subcutaneous), as a skin patch (transdermal), or as an implant. For opioid use disorder, it is typically started when withdrawal symptoms have begun and for the first two days of treatment under direct observation of a health-care provider. In the United States, the combination formulation of buprenorphine/naloxone (Suboxone) is usually prescribed to discourage misuse by injection. Maximum pain relief is generally within an hour with effects up to 24 hours. Buprenorphine affects different types of opioid receptors in different ways. Depending on the type of receptor, it may be an agonist, partial agonist, or antagonist.  In the treatment of opioid use disorder buprenorphine is an agonist/antagonist, meaning that it relieves withdrawal symptoms from other opioids and induces some euphoria, but also blocks the ability for many other opioids, including heroin, to cause an effect.  Unlike full agonists like heroin or methadone, buprenorphine has a ceiling effect, such that taking more medicine will not increase the effects of the drug.Side effects may include respiratory depression (decreased breathing), sleepiness, adrenal insufficiency, QT prolongation, low blood pressure, allergic reactions, constipation, and opioid addiction. Among those with a history of seizures,  a risk exists of further seizures. Opioid withdrawal following stopping buprenorphine is generally less severe than with other opioids. Whether use during pregnancy is safe is unclear, but use while breastfeeding is probably safe, since the dose the infant receives is 1-2% that of the maternal dose, on a weight basis.Buprenorphine was patented in 1965, and approved for medical use in the United States in 1981. It is on the World Health Organizations List of Essential Medicines. In addition to prescription as an analgesic it is  a common medication used to treat opioid use disorders, such as addiction to heroin. In 2017, 14.6 million prescriptions for the medication were written in the United States. Buprenorphine may also be used recreationally for the high it produces, and in the US sublingual formulations are marketed as a film or mixed with naloxone to discourage injection. In the United States, buprenorphine is a schedule III controlled substance.

Medical uses
Opioid use disorder
Buprenorphine is used to treat people with opioid use disorder.: 84–7  In the U.S., the combination formulation of buprenorphine/naloxone is generally prescribed to deter injection, since naloxone, an opioid antagonist, causes acute withdrawal if the formulation is crushed and injected.: 99  However, taken orally, the nalaxone has virtually no effect, due to the drugs extremely high first-pass metabolism and low bioavailability (2%). Before starting buprenorphine, individuals are generally advised to wait long enough after their last dose of opioid until they have some withdrawal symptoms to allow for the medication to bind the receptors,since if taken too soon, buprenorphine can displace other opioids bound to the receptors and precipitate an acute withdrawal. The dose of buprenorphine is then adjusted until symptoms improve, and individuals remain on a maintenance dose of 8–16 mg.: 99–100   Because withdrawal is uncomfortable and a deterrent for many patients, many have begun to call for different means of treatment initiation.  Some providers have begun to use the Bernese method, also known as microdosing, in which very small doses of buprenorphine are given while patients are still using street opioids, and without precipitating withdrawal, with medicine levels slowly titrated upward.

Buprenorphine versus methadone
Both buprenorphine and methadone are medications used for detoxification and opioid replacement therapy, and appear to have similar effectiveness based on limited data. Both are safe for pregnant women with opioid use disorder,: 101  although preliminary evidence suggests that methadone is more likely to cause neonatal abstinence syndrome. In the US and European Union, only designated clinics can prescribe methadone for opioid use disorder, requiring patients to travel to the clinic daily. If patients are drug free for a period they may be permitted to receive "take home doses," reducing their visits to as little as once a week. Alternatively, up to a months supply of buprenorphine has been able to be prescribed by clinicians in the US or Europe who have completed a basic training (8–24 hours in the US) and received a waiver/licence allowing prescription of the medicine.: 84–5   In France, buprenorphine prescription for opioid use disorder has been permitted without any special training or restrictions since 1995, resulting in treatment of approximately ten times more patients per year with buprenorphine than with methadone in the following decade. In 2021, seeking to address record levels of opioid overdose, the United States also removed the requirement for a special waiver for prescribing physicians. Whether this change will be sufficient to impact prescription is unclear, since even before the change as many as half of physicians with a waiver permitting them to prescribe buprenorphine did not do so, and one third of non-waivered physicians reported that nothing would induce them to prescripe buprenorphine for opioid use disorder.

Chronic pain
A transdermal patch is available for the treatment of chronic pain. These patches are not indicated for use in acute pain, pain that is expected to last only for a short period of time, or pain after surgery, nor are they recommended for opioid addiction.

Potency
With respect to equianalgesic dosing, when used sublingually, the potency of buprenorphine is about 40 to 70 times that of morphine. When used as a transdermal patch, the potency of buprenorphine may be 100 to 115 times that of morphine.

Veterinary uses
Veterinarians frequently administer buprenorphine for perioperative pain, particularly in cats, where its effects are similar to morphine. The drugs legal status and lower potential for human abuse makes it an attractive alternative to other opioids.

Adverse effects
Common adverse drug reactions associated with the use of buprenorphine, similar to those of other opioids, include nausea and vomiting, drowsiness, dizziness, headache, memory loss, cognitive and neural inhibition, perspiration, itchiness, dry mouth, shrinking of the pupils of the eyes (miosis), orthostatic hypotension, male ejaculatory difficulty, decreased libido, and urinary retention. Constipation and central nervous system (CNS) effects are seen less frequently than with morphine.

Respiratory effects
The most severe side effect associated with buprenorphine is respiratory depression (insufficient breathing). It occurs more often in those who are also taking benzodiazepines or alcohol, or have underlying lung disease. The usual reversal agents for opioids, such as naloxone, may be only partially effective, and additional efforts to support breathing may be required. Respiratory depression may be less than with other opioids, particularly with chronic use. In the setting of acute pain management, though, buprenorphine appears to cause the same rate of respiratory depression as other opioids such as morphine.

Buprenorphine dependence
Buprenorphine treatment carries the risk of causing psychological or physiological (physical) dependencies. It has a slow onset of activity, with a long duration of action, and a long half-life of 24 to 60 hours. Once a patient has stabilised on the (buprenorphine) medication and programme, three options remain - continual use (buprenorphine-only medication), switching to a buprenorphine/naloxone combination, or a medically supervised withdrawal.

Pain management
Achieving acute opioid analgesia is difficult in persons using buprenorphine for pain management.

Pharmacology
Pharmacodynamics
Opioid receptor modulator
Buprenorphine has been reported to possess these following pharmacological activities:
μ-Opioid receptor (MOR): Very high affinity partial agonist: at low doses, the MOR-mediated effects of buprenorphine are comparable to those of other narcotics, but these effects reach a "ceiling" as the receptor population is saturated. This behavior is responsible for several unique properties: buprenorphine greatly reduces the effect of most other MOR agonists, can cause precipitated withdrawal when used in actively opioid dependent persons, and has a lower incidence of respiratory depression and fatal overdose relative to full MOR agonists.
κ-Opioid receptor (KOR): High affinity antagonist—this activity is hypothesized to underlie some of the effects of buprenorphine on mood disorders and addiction.
δ-Opioid receptor (DOR): High affinity antagonist
Nociceptin receptor (NOP, ORL-1): Weak affinity, very weak partial agonistIn simplified terms, buprenorphine can essentially be thought of as a nonselective, mixed agonist–antagonist opioid receptor modulator, acting as an unusually high affinity weak partial agonist of the MOR, a high affinity antagonist of the KOR and DOR, and a relatively low affinity, very weak partial agonist of the ORL-1/NOP.Although buprenorphine is a partial agonist of the MOR, human studies have found that it acts like a full agonist with respect to analgesia in opioid-intolerant individuals. Conversely, buprenorphine behaves like a partial agonist of the MOR with respect to respiratory depression.Buprenorphine is also known to bind to with high affinity and antagonize the putative ε-opioid receptor.Full analgesic efficacy of buprenorphine requires both exon 11- and exon 1-associated μ-opioid receptor splice variants.The active metabolites of buprenorphine are not thought to be clinically important in its CNS effects.In positron emission tomography (PET) imaging studies, buprenorphine was found to decrease whole-brain MOR availability due to receptor occupancy by 41% (i.e., 59% availability) at 2 mg, 80% (i.e., 20% availability) at 16 mg, and 84% (i.e., 16% availability) at 32 mg.

Other actions
Unlike some other opioids and opioid antagonists, buprenorphine binds only weakly to and possesses little if any activity at the sigma receptor.Buprenorphine also blocks voltage-gated sodium channels via the local anesthetic binding site, and this underlies its potent local anesthetic properties.Similarly to various other opioids, buprenorphine has also been found to act as an agonist of the toll-like receptor 4, albeit with very low affinity.

Pharmacokinetics
Buprenorphine is metabolized by the liver, via CYP3A4 (also CYP2C8 seems to be involved) isozymes of the cytochrome P450 enzyme system, into norbuprenorphine (by N-dealkylation). The glucuronidation of buprenorphine is primarily carried out by UGT1A1 and UGT2B7, and that of norbuprenorphine by UGT1A1 and UGT1A3. These glucuronides are then eliminated mainly through excretion into bile. The elimination half-life of buprenorphine is 20 to 73 hours (mean 37 hours). Due to the mainly hepatic elimination,  no risk of accumulation exists in people with renal impairment.One of the major active metabolites of buprenorphine is norbuprenorphine, which, in contrast to buprenorphine itself, is a full agonist of the MOR, DOR, and ORL-1, and a partial agonist at the KOR. However, relative to buprenorphine, norbuprenorphine has extremely little antinociceptive potency (1/50th that of buprenorphine), but markedly depresses respiration (10-fold more than buprenorphine). This may be explained by very poor brain penetration of norbuprenorphine due to a high affinity of the compound for P-glycoprotein. In contrast to norbuprenorphine, buprenorphine and its glucuronide metabolites are negligibly transported by P-glycoprotein.The glucuronides of buprenorphine and norbuprenorphine are also biologically active, and represent major active metabolites of buprenorphine. Buprenorphine-3-glucuronide has affinity for the MOR (Ki = 4.9 pM), DOR (Ki = 270 nM) and ORL-1 (Ki = 36 μM), and no affinity for the KOR. It has a small antinociceptive effect and no effect on respiration. Norbuprenorphine-3-glucuronide has no affinity for the MOR or DOR, but does bind to the KOR (Ki = 300 nM) and ORL-1 (Ki = 18 μM). It has a sedative effect but no effect on respiration.

Chemistry
Buprenorphine is a semisynthetic derivative of thebaine, and is fairly soluble in water, as its hydrochloride salt. It degrades in the presence of light.

Detection in body fluids
Buprenorphine and norbuprenorphine may be quantified in blood or urine to monitor use or non-medical recreational use, confirm a diagnosis of poisoning, or assist in a medicolegal investigation. A significant overlap of drug concentrations exists in body fluids within the possible spectrum of physiological reactions ranging from asymptomatic to comatose. Therefore, having knowledge of both the route of administration of the drug and the level of tolerance to opioids of the individual is critical when results are interpreted.

History
In 1969, researchers at Reckitt and Colman (now Reckitt Benckiser) had spent 10 years attempting to synthesize an opioid compound "with structures substantially more complex than morphine [that] could retain the desirable actions whilst shedding the undesirable side effects". Physical dependence and withdrawal from buprenorphine itself remain important issues, since buprenorphine is a long-acting opioid. Reckitt found success when researchers synthesized RX6029 which had showed success in reducing dependence in test animals. RX6029 was named buprenorphine and began trials on humans in 1971. By 1978, buprenorphine was first launched in the UK as an injection to treat severe pain, with a sublingual formulation released in 1982.

Society and culture
Regulation
United States
In the United States, buprenorphine and buprenorphine with naloxone were approved for opioid use disorder by the Food and Drug Administration in October 2002. The DEA rescheduled buprenorphine from a schedule V drug to a schedule III drug just before approval. The ACSCN for buprenorphine is 9064, and being a schedule III substance, it does not have an annual manufacturing quota imposed by the DEA. The salt in use is the hydrochloride, which has a free-base conversion ratio of 0.928.
In the years before buprenorphine/naloxone was approved, Reckitt Benckiser had lobbied Congress to help craft the Drug Addiction Treatment Act of 2000, which gave authority to the Secretary of Health and Human Services to grant a waiver to physicians with certain training to prescribe and administer schedule III, IV, or V narcotic drugs for the treatment of addiction or detoxification. Before this law was passed, such treatment was permitted only in clinics designed specifically for drug addiction.The waiver, which can be granted after the completion of an eight-hour course, was required for outpatient treatment of opioid addiction with buprenorphine from 2000 to 2021. Initially, the number of people each approved physician could treat was limited to 10. This was eventually modified to allow approved physicians to treat up to 100 people with buprenorphine for opioid addiction in an outpatient setting. This limit was increased by the Obama administration, raising the number of patients to which doctors can prescribe to 275. On 14 January 2021, the US Department of Health and Human Services announced that the waiver would no longer be required to prescribe buprenorphine to treat up to 30 people concurrently.New Jersey authorized paramedics to give buprenorphine to people at the scene after they have recovered from an overdose.

Europe
In the European Union, Subutex and Suboxone, buprenorphines high-dose sublingual tablet preparations, were approved for opioid use disorder treatment in September 2006. In the Netherlands, buprenorphine is a list II drug of the Opium Law, though special rules and guidelines apply to its prescription and dispensation. In France, where buprenorphine prescription by general practitioners and dispensed by pharmacies has been permitted since the mid-1990s as a response to HIV and overdose risk </s>