Find & Manage Your Patient Assistance Programs
Estimated patient savings $600,000,000.00

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.





Clarithromycin is an antibiotic used to treat a wide variety of bacterial infections such as respiratory tract infections and skin infections. It is also used to treat peptic ulcers in combination with anti-ulcer medication. It is also used to treat ear infections in children.

How To Use

Regular release clarithromycin tablets may be taken with or without food. If stomach upset occurs, try taking it with food. Extended release tablets (XL) must be taken with food and swallowed whole. Do not crush or chew them. Antibiotics work best when the amount of medicine in your body is kept at a constant level. Do this by taking the medication at the same time(s) each day. Continue to take this medication until the full prescribed amount is finished, even if symptoms disappear after a few days. Stopping the medication too early may allow bacteria to continue to grow resulting in a relapse of the infection.

Side Effects

This medication may cause stomach upset, nausea, indigestion, loose stools, loss of appetite, vomiting, headache, or a strange taste in the mouth the first few days as your body adjusts to it. If these symptoms continue or become severe, inform your doctor. If you develop diarrhea while taking this medication, notify your doctor. Do not take any nonprescription medications to treat diarrhea without first consulting your doctor or pharmacist. Unlikely but report promptly: dark urine, yellowing eyes/skin, severe stomach pain, mental/mood changes, an irregular heartbeat. In the unlikely event you have an allergic reaction to this drug, seek medical attention immediately. Symptoms of an allergic reaction include: rash, itching, swelling, dizziness, trouble breathing. Use of this medication for prolonged or repeated periods may result in a secondary infection (e.g., oral, bladder or vaginal yeast infection). If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor your medical history, especially of: other illnesses, allergies (especially drug allergies), liver disease, colitis, stomach problems, kidney problems, heart disease. This medication is not recommended for use during pregnancy except when no other antibiotic can be used. This drug can potentially cause fetal harm. Consult your doctor for more details. Small amounts of drug do appear in breast milk, so consult your doctor before breast-feeding.

Drug Interactions

This drug should not be used with the following medications because very serious, possibly fatal, interactions may occur: cisapride, pimozide, astemizole, terfenadine. If you are currently using any of these medications, tell your doctor or pharmacist before starting clarithromycin. Before using this medicine, tell your doctor of all prescription and nonprescription products you may use, especially of: barbiturates, benzodiazepines (e.g., alprazolam, midazolam, triazolam), carbamazepine, certain protease inhibitors (e.g., lopinavir, ritonavir), cyclosporine, digoxin, ergotamine (and related drugs), certain live vaccines, omeprazole, phenytoin, theophylline, warfarin, zidovudine, certain drugs for high cholesterol (e.g., lovastatin, simvastatin), sildenafil, tacrolimus, alfentanil, rifabutin, methylprednisolone, cilostazol, bromocriptine, valproate, tolterodine. Other drugs besides clarithromycin which may affect the heart rhythm (QTc prolongation in the EKG) include dofetilide, disopyramide, quinidine, droperidol, sotalol, procainamide, and sparfloxacin among others. QTc prolongation can infrequently result in serious, rarely fatal, irregular heartbeats. Consult your doctor or pharmacist for details. Ask for instructions about whether you need to stop any other QTc-prolonging drugs you may be using in order to minimize the risk of this effect. This drug may interfere with the effectiveness of birth control pills. Discuss using other methods of birth control with your doctor. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include nausea, vomiting, and diarrhea.


This medication has been prescribed for your current condition only. Do not use it later for another infection or give it to someone else. A different medication may be necessary.

Missed Dose

If you miss a dose, do not double dose. Take the missed dose as soon as you remember unless it is nearly time for the next dose. If it is nearly time for the next dose, skip the missed dose and resume your usual dosing schedule.


Store at room temperature between 68 and 77 degrees F (20 to 25 degrees C) away from moisture and sunlight. Do not store in the bathroom.