Clarithromycin is used to treat certain bacterial infections, such as pneumonia (a lung infection), bronchitis (infection of the tubes leading to the lungs), and infections of the ears, sinuses, skin, and throat. It also is used to treat and prevent disseminated Mycobacterium avium complex (MAC) infection [a type of lung infection that often affects people with human immunodeficiency virus (HIV)]. It is used in combination with other medications to eliminate H. pylori, a bacterium that causes ulcers. Clarithromycin is in a class of medications called macrolide antibiotics. It works by stopping the growth of bacteria.
Antibiotics such as clarithromycin will not work for colds, flu, or other viral infections. Taking antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment.
Side Effects Of Clarithromycin
Clarithromycin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- stomach pain
- change in taste
Some side effects of clarithromycin can be serious. If you experience any of the following symptoms, call your doctor immediately or get emergency medical treatment:
- chest pain, shortness of breath, trouble breathing, pain or weakness in the side of your body, or slurred speech
- severe diarrhea with watery or bloody stools (up to 2 months after your treatment)
- swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
- difficulty breathing or swallowing
- peeling or blistering skin
- yellowing of the skin or eyes
- extreme tiredness
- unusual bleeding or bruising
- lack of energy
- loss of appetite
- pain in the upper right part of the stomach
- dark-colored urine
- flu-like symptoms
- fast, pounding, or irregular heartbeat
- muscle weakness such as difficulty chewing, talking or performing daily activities
- double vision
Clarithromycin may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
Warnings & Precautions
Before taking clarithromycin:
- tell your doctor and pharmacist if you are allergic to clarithromycin, azithromycin (Zithromax, Zmax), erythromycin (E.E.S., Eryc, Erythrocin, PCE, others), telithromycin (not available in the U.S.; Ketek), any other medications, or any of the ingredients in clarithromycin preparations. Ask your pharmacist for a list of the ingredients.
- tell your doctor if you are taking cisapride (Propulsid; not available in the U.S.), colchicine (Colcrys, Mitigare) if you have kidney or liver disease, dihydroergotamine (D.H.E. 45, Migranal), ergotamine (Ergomar, in Cafergot, in Migergot), lomitapide (Juxtapid), lovastatin (in Advicor), pimozide (Orap), or simvastatin (Flolipid, Zocor, in Vytorin). Your doctor will probably tell you not to take clarithromycin if you are taking one or more of these medications.
- tell your doctor if you have or have ever had jaundice (yellowing of the skin or eyes) or other liver problems while taking clarithromycin. Your doctor will probably tell you not to take clarithromycin.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take with clarithromycin. Be sure to mention any of the following: anticoagulants (‘blood thinners’) such as warfarin (Coumadin, Jantoven); certain benzodiazepines such as alprazolam (Xanax), midazolam, and triazolam (Halcion); bromocriptine (Parlodel); calcium channel blockers such as amlodipine (Norvasc, in Caduet, in Lotrel), diltiazem (Cardizem, Cartia, Tiazac), nifedipine (Adalat, Afeditab CR), and verapamil (Calan, Verelan, in Tarka, others); carbamazepine (Epitol, Tegretol, Teril, others); colchicine (Colcrys, Mitigare); certain medications for HIV such as atazanavir (Reyataz), didanosine (Videx), efavirenz (Sustiva, in Atripla), etravirine (Intelence), nevirapine (Viramune), nelfinavir (Viracept), ritonavir (Norvir, in Kaletra), saquinavir (Invirase), and zidovudine (AZT, Retrovir); certain medications for irregular heartbeat such as amiodarone (Pacerone), disopyramide (Norpace), dofetilide (Tikosyn), procainamide, quinidine (in Nuedexta), and sotalol (Betapace, Sorine); cholesterol-lowering medications (statins) such as atorvastatin (Lipitor, in Caduet), and pravastatin (Pravachol); cilostazol; cyclosporine (Gengraf, Neoral, Sandimmune); darifenacin (Enablex); digoxin (Digitek, Lanoxin); erlotinib (Tarceva); eszopiclone (Lunesta); fluconazole (Diflucan); insulin; itraconazole (Onmel, Sporanox); maraviroc (Selzentry); methylprednisolone (Medrol); omeprazole (Prilosec); oral medications for diabetes such as nateglinide (Starlix), pioglitazone (Actos, in Actoplus Met, in Duetact), repaglinide (Prandin, in Prandimet), and rosiglitazone (Avandia, in Avandamet, in Avandaryl); phenobarbital; phenytoin (Dilantin, Phenytek); quetiapine (Seroquel); ranitidine (Zantac); rifabutin (Mycobutin); rifampin (Rifadin, Rimactane, in Rifater, in Rifamate); rifapentine (Priftin); sildenafil (Revatio, Viagra); tacrolimus (Astagraf, Prograf); theophylline (Elixophyllin, Theo-24, Theochron); tadalafil (Adcirca, Cialis); tolterodine (Detrol); valproate (Depacon); vardenafil (Levitra, Staxyn); and vinblastine. Many other medications may also interact with clarithromycin, so tell your doctor about all the medications you are taking, even those that do not appear on this list. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor what herbal products you are taking, especially St. John’s wort.
- tell your doctor if you have or have ever had a prolonged QT interval (a rare heart problem that may cause fainting or irregular heartbeat), ventricular arrhythmia (abnormal heart rhythms), a low level of magnesium or potassium in your blood, myasthenia gravis (MG; a disorder of the nervous system that causes muscle weakness), or if you have or have ever had an irregular heartbeat, coronary artery disease (narrowing of the blood vessels that supply blood to the heart), or kidney, or liver disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking clarithromycin, call your doctor. Clarithromycin may harm the fetus.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking clarithromycin.
- you should know that clarithromycin may make you dizzy, confused, or disoriented. Do not drive a car or operate machinery until you know how this medication affects you.
Dosage Of Clarithromycin
Clarithromycin comes as a tablet, an extended-release (long-acting) tablet, and a suspension (liquid) to take by mouth. The regular tablet and liquid are usually taken with or without food every 8 (three times a day) to 12 hours (twice a day) for 7 to 14 days. The extended-release tablet is usually taken with food every 24 hours (once a day) for 7 to 14 days. Your doctor may tell you to take clarithromycin for a longer time depending on your condition. Take clarithromycin at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take clarithromycin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Shake the suspension well before each use to mix the medication evenly.
Swallow the long-acting tablets whole; do not split, chew, or crush them.
You should begin to feel better during the first few days of treatment with clarithromycin. If your symptoms do not improve or get worse, call your doctor.
Take clarithromycin until you finish the prescription, even if you feel better. If you stop taking clarithromycin too soon or skip doses, your infection may not be completely treated and the bacteria may become resistant to antibiotics.
Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body’s response to clarithromycin.
The extended-release tablet does not dissolve in the stomach after swallowing. It slowly releases the medication as it passes through your digestive system. You may notice the tablet coating in the stool. This is normal and does not mean that you did not get the full dose of medication.
Do not let anyone else take your medication. Your prescription is probably not refillable. If you still have symptoms of infection after you finish the clarithromycin, call your doctor.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
All information has been provided courtesy of MedLinePlus from the National Library of Medicine and from the FDA.