Telithromycin should not be used in patients with myasthenia gravis. It may cause the condition to become worse. There have been reports of severe (possibly fatal) breathing problems in patients with myasthenia gravis who took telithromycin.Who should not take Ketek?
This medication is a ketolide antibiotic used to treat a type of pneumonia caused by bacteria. It will not work for viral infections (e.g., common cold, flu). Unnecessary use or overuse of any antibiotic can lead to its decreased effectiveness.
Read the Medication Guide and, if available, the Patient Information Leaflet provided by your pharmacist before you start using telithromycin and each time you get a refill. If you have any questions regarding the information, consult your doctor or pharmacist.
Take this medication by mouth with or without food as directed by your doctor, usually once daily.
The dosage is based on your medical condition and response to treatment.
Antibiotics work best when the amount of medicine in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals.
Continue to take this medication until the full prescribed amount is finished, even if symptoms disappear after a few days. Stopping this medication too early may result in a return of the infection.
Tell your doctor if your condition persists or worsens.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Telithromycin may rarely cause very serious liver disease. Seek immediate medical attention if you develop: extreme tiredness, loss of appetite, stomach/abdominal pain, dark urine, yellowing eyes/skin.
This medication may rarely cause a severe intestinal condition (Clostridium difficile-associated diarrhea) due to resistant bacteria. This condition may occur weeks to months after treatment has stopped. Do not use anti-diarrhea products or narcotic pain medications if you have the following symptoms because these products may make them worse. Tell your doctor right away if you develop persistent diarrhea, abdominal or stomach pain/cramping, or blood/mucus in your stool.
Use of this medication for prolonged or repeated periods may result in oral thrush or a new vaginal yeast infection (oral or vaginal fungal infection). Contact your doctor if you notice white patches in your mouth, a change in vaginal discharge, or other new symptoms.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any of the following symptoms of a serious allergic reaction: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before taking telithromycin, tell your doctor or pharmacist if you are allergic to it; or to macrolide antibiotics (e.g., azithromycin, clarithromycin, dirithromycin, erythromycin); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: myasthenia gravis, kidney disease (including dialysis), liver problems (such as hepatitis, especially if it occurred while taking telithromycin or a macrolide antibiotic).
Telithromycin may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.
The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using telithromycin, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).
Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using telithromycin safely.
This medication may cause vision problems, dizziness, or fainting. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Limit alcoholic beverages.
Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above).
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug include: digoxin, ergot drugs (e.g., dihydroergotamine, ergotamine), ivabradine, live bacterial vaccines (e.g., typhoid or cholera vaccines), metoprolol, certain "statin" drugs for high cholesterol (atorvastatin, lovastatin, simvastatin), theophylline, warfarin.
Telithromycin can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include colchicine, cyclosporine, eletriptan, eplerenone, lurasidone, midazolam, regorafenib, rilpivirine, sildenafil, simeprevir, tacrolimus, ticagrelor, triazolam, among others.
Other medications can affect the removal of telithromycin from your body, which may affect how telithromycin works. Examples include certain azole antifungals (such as itraconazole, ketoconazole), rifamycins (such as rifampin, rifabutin), St. John's wort, drugs used to treat seizures (such as carbamazepine, phenytoin), among others.
Many drugs besides telithromycin may affect the heart rhythm (QT prolongation), including amiodarone, cisapride, dofetilide, pimozide, procainamide, quinidine, sotalol, macrolide antibiotics (such as erythromycin), among others. Therefore, before using telithromycin, report all medications you are currently using to your doctor or pharmacist.
Although most antibiotics are unlikely to affect hormonal birth control such as pills, patch, or ring, a few antibiotics (such as rifampin, rifabutin) can decrease their effectiveness. This could result in pregnancy. If you use hormonal birth control, ask your doctor or pharmacist for more details.
If overdose is suspected, contact a poison control center or emergency room right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: irregular/fast heartbeat, fainting.
Do not share this medication with others.
This medication has been prescribed for your current condition only. Do not use it later for another infection unless told to do so by your doctor. A different medication may be necessary in that case.
Laboratory and/or medical tests (e.g., liver function tests) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised September 2015. Copyright(c) 2015 First Databank, Inc.
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