What is it used for?
- Community-acquired pneumonia (ie, pneumonia not contracted in hospital) in adults aged 18 years and over.
- Acute sinusitis caused by bacteria that are resistant to penicillin, cephalosporin and other macrolide type antibiotics in adults aged 18 years and over.
- Acute flare-ups of chronic bronchitis caused by bacteria that are resistant to penicillin, cephalosporin and other macrolide type antibiotics in adults aged 18 years and over.
- Tonsillitis/pharyngitis caused by a type of bacteria called Streptococcus pyogenes, in adults and children aged 12 years and over, when other antibiotics are not appropriate.
How does it work?
Ketek tablets contain the active ingredient telithromycin, which is a type of medicine called a macrolide antibiotic. It is used to treat infections caused by bacteria.
Telithromycin works by preventing bacteria from producing proteins that are essential to them. Without these proteins the bacteria cannot grow, replicate and increase in numbers. By controlling bacterial numbers, telithromycin stops the spread of infection and the remaining bacteria eventually die or are killed by the body's immune system. This treats the infection.
Telithromycin is used to treat bacterial infections affecting the lungs and airways (respiratory tract), such as pneumonia, sinusitis and bronchitis.
To make sure the bacteria causing an infection are susceptible to telithromycin your doctor may take a tissue sample, for example a swab from the throat or sputum sample.
How do I take it?
- The dose of this medicine and how long it needs to be taken for depends on the type of infection you have and your kidney function. Follow the instructions given by your doctor. These will be printed on the dispensing label that your pharmacist has put on the packet of medicine.
- Ketek tablets are usually taken once a day, preferably at bedtime (see warning below).
- The tablets should be swallowed whole with water. They can be taken either with or without food.
- Unless your doctor tells you otherwise, it is important that you finish the prescribed course of this antibiotic medicine, even if you feel better or it seems the infection has cleared up. Stopping the course early increases the chance that the infection will come back and that the bacteria will grow resistant to the antibiotic.
- This medicine may cause various side effects that could impair your ability to safely drive, operate machinary or perform other potentially hazardous activites. For example, some people may experience visual disturbances such as blurred or double vision or difficulty focusing, and on rare occasions some people have temporarily lost conciousness (fainted). These side effects can occur as soon as after the first dose. For this reason you should avoid, or at least minimise, activities such as driving, operating heavy machinery or taking part in other hazardous activities while you are taking this medicine. It is best to take your daily dose of this medicine at bedtime, so that the potential impact of any of these side effects is minimised if you do experience them. If you do experience any problems with your vision or loss of conciousness you should not drive or operate machinery.
- Broad-spectrum antibiotics can sometimes cause inflammation of the bowel (colitis). For this reason, if you get diarrhoea that becomes severe or persistent or contains blood or mucus, either during or after taking this medicine, you should consult your doctor immediately.
- All antibiotics can sometimes result in overgrowth of organisms that are not susceptible to the antibiotic, in particular fungi. You should let your doctor know if you think you have developed any other infections while you are taking this medicine, so that they can be treated appropriately.
- This medicine may rarely cause liver problems. For this reason, you should consult your doctor promptly if you experience symptoms that could suggest a liver problem while you are taking this medicine. These symptoms might include unexplained itching, nausea and vomiting, abdominal pains, loss of appetite or flu-like symptoms, yellowing of the skin or eyes (jaundice), or unusually dark urine.
Use with caution in
- Decreased kidney function.
- Decreased liver function.
- Coronary heart disease.
- History of irregular heart beats (ventricular arrhythmias).
- Slow heart rate of less than 50 beats per minute (bradycardia).
- People with an imbalance of salts in the blood, particularly low blood potassium levels (hypokalaemia) or low blood magnesium levels (hypomagnesemia).
- People taking medicines that can increase the risk of a type of abnormal heart rhythm, seen on a heart monitoring trace (ECG) as a 'prolonged QT interval' (see end of factsheet for examples).
Not to be used in
- People allergic to macrolide type antibiotics, eg erythromycin, clarithromycin.
- People who have experienced inflammation of the liver (hepatitis) or jaundice during previous treatment with telithromycin.
- Abnormal muscle weakness (myasthenia gravis).
- People with a personal or family history of a type of abnormal heart rhythm, seen on a heart monitoring trace (ECG) as a 'prolonged QT interval'.
- People taking the medicines astemizole, cisapride, ergotamine, dihdyroergotamine, pimozide, atorvastatin, simvastatin or terfenadine (see end of page for more information).
- This medicine is not recommended for children under 12 years of age, because its safety and effectiveness have not been established in this age group.
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy. If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Pregnancy and breastfeeding
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
- The safety of this medicine for use during pregnancy has not been established. It is not recommended for use in pregnancy unless considered essential by your doctor. Seek medical advice from your doctor.
- There is no information available about the safety of this medicine during breastfeeding. For this reason, the manufacturer states that it should not be used to treat women who are breastfeeding. Seek medical advice from your doctor.
- Take at regular intervals. Complete the prescribed course unless otherwise directed.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
Very common (affect more than 1 in 10 people)
Common (affect between 1 in 10 and 1 in 100 people)
- Alteration in taste.
- Disturbances of the gut such as nausea, vomiting, abdominal pain or flatulence (wind).
- Vaginal thrush.
Uncommon (affect between 1 in 100 and 1 in 1000 people)
- Oral thrush.
- Awareness of your heartbeat (palpitations).
- Inflammation of the liver (hepatitis).
- Sleepiness (somnolence).
- Difficulty sleeping (insomnia).
- Loss of appetite.
- Inflammation of the lining of the mouth (stomatitis).
- Blurred vision.
- Rash or itching.
Rare (affect between 1 in 1000 and 1 in 10,000 people)
- Double vision.
- Temporary loss of conciousness (fainting).
- Pins and needles sensations.
- Abnormal heart beats (arrhythmias).
- Low blood pressure (hypotension).
Very rare (affect less than 1 in 10,000 people)
- Inflammation of the large intestine (colitis) - see warning section above.
- Muscle cramps.
- Change in sense of smell.
The side effects listed above may not include all of the side effects reported by the medicine's manufacturer. For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
How can this medicine affect other medicines?
It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, ask your doctor or pharmacist before taking any new medicines while taking this one, so they can check that the combination is safe.
Telithromycin must not be taken by people taking any of the following medicines, because the combination may result in an increased risk of serious side effects:
- ergot alkaloids, eg ergotamine, dihydroergotamine, methysergide
Telithromycin may increase the blood levels of statins used for lowering cholesterol and this could increase the risk of side effects from the statin. If you are taking simvastatin, lovastatin or atorvastatin you will need to stop taking it during treatment with this antibiotic and restart it again after the antibiotic course is completed. If you are taking another statin, eg pravastatin, fluvastatin, rosuvastatin, you can continue taking it while taking this antibiotic, but you should let your doctor know if you get any new or increased side effects, in particular any muscle pain or weakness.
Telithromycin may also increase the blood levels of the medicines listed below and so could increase the risk of their side effects. If you are taking one of these medicines and are prescribed telithromycin you should let your doctor or pharmacist know if you experience any new or increased side effects:
- the benzodiazepines midazolam, triazolam and alprazolam (telithromycin should not be used in combination with midazolam taken by mouth)
- digoxin (your doctor may want to monitor your digoxin blood level while you are taking this antibiotic)
- the immunosuppressants ciclosporin, tacrolimus and sirolimus. (If you are taking any of these your doctor will need to check the blood level of your immunosuppressant when you start taking this antibiotic and after the course is finished. Your immunosuppressant dose may need adjusting.)
- vardenafil, sildenafil or tadalafil for erectile dysfunction (your doctor may suggest you use a lower dose while you are taking this antibiotic).
Telithromycin should ideally not be used to treat people taking any of the following medicines, or who have taken any of these in the previous two weeks, because they may make the antibiotic less effective:
- the herbal remedy St John's wort (Hypericum perforatum).
Telithromycin may increase the anti-blood-clotting effect of anticoagulants such as warfarin. If you are taking an anticoagulant medicine your doctor may want to do extra monitoring of your blood clotting time (INR) while you are taking this antibiotic.
Protease inhibitors for treating HIV infection, such as ritonavir, may increase the blood level of telithromycin. As this may increase the risk of its side effects, telithromycin should be used with caution in people taking protease inhibitors. If you have severe liver or kidney disease and are taking a protease inhibitor, you should not be prescribed telithromycin.
Antifungal medicines such as ketoconazole and itraconazole may also increase the blood level of telithromycin. They should not be used in combination with telithromycin in people who have severe liver or kidney disease.
Telithromycin should be used with caution in people taking any of the following medicines, because the combination may increase the risk of abnormal heart rhythms (prolonged QT interval on a heart monitoring trace or ECG):
- anti-arrhythmics, eg amiodarone, procainamide, disopyramide, sotalol
- certain antimalarials, eg halofantrine, chloroquine, quinine, Riamet, mefloquine
- certain antipsychotics, eg amisulpride, thioridazine, chlorpromazine, sertindole, haloperidol.
If you are taking theophylline in combination with this antibiotic, your doses of the two medicines should be separated by one hour. This is to avoid possible digestive side effects such as nausea and vomiting.
Oral typhoid vaccine (Vivotif) should not be taken until at least three days after you have finished a course of this antibiotic, because the antibiotic could make this vaccine less effective.
Other medicines containing the same active ingredient
There are currently no other medicines available in the UK that contain telithromycin as the active ingredient.