Do NOT use Biaxin if:

• you are allergic to any ingredient in Biaxin or to any other macrolide (eg, erythromycin)
• you are taking cisapride, cyclosporine, dofetilide, eletriptan, an ergot alkaloid (eg, dihydroergotamine, ergotamine), an H₁ antagonist (eg, astemizole, terfenadine), pimozide, a QT-prolonging agent (eg, quinidine, sotalol, thioridazine), a quinolone (eg, ciprofloxacin), or sumatriptan.

Contact your doctor or health care provider right away if any of these apply to you.

Some medical conditions may interact with Biaxin. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

• if you are pregnant, planning to become pregnant, or are breast-feeding
• if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
• if you have allergies to medicines, foods, or other substances
• if you have diarrhea, a stomach infection, a blood disorder, severe kidney problems, or liver problems.

Some medicines may interact with Biaxin. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Aldosterone blockers (eg, spironolactone), anticoagulants (eg, warfarin), benzodiazepines (eg, alprazolam), buspirone, carbamazepine, cilostazol, cisapride, colchicine, corticosteroids (eg, hydrocortisone), cyclosporine, digoxin, disopyramide, eletriptan, ergot alkaloids (eg, ergotamine, dihydroergotamine), H₁ antagonists (eg, astemizole, terfenadine), HMG-CoA reductase inhibitors (eg, simvastatin), imatinib, macrolide immunosuppressants (eg, tacrolimus), macrolides and ketolides (eg, azithromycin, erythromycin), phosphodiesterase type 5 inhibitors (eg, sildenafil), rifampin, sumatriptan, theophyllines, or verapamil because their actions and the risk of their side effects may be increased by Biaxin
• Dofetilide, macrolides and ketolides (eg, azithromycin, erythromycin), pimozide, QT-prolonging agents (eg, quinidine, sotalol, thioridazine), quinolones (eg, ciprofloxacin), or streptogramins (eg, mikamycin) because serious, possibly life-threatening side effects on the heart or irregular heartbeat may occur
• Rifampin because it may decrease Biaxin's effectiveness.

This may not be a complete list of all interactions that may occur. Ask your health care provider if Biaxin may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

Important safety information:

• Biaxin only works against bacteria; it does not treat viral infections (eg, the common cold).
• Long-term or repeated use of Biaxin may cause a second infection. Tell your doctor if signs of a second infection occur. Your medicine may need to be changed to treat this.
• Be sure to use Biaxin for the full course of treatment. If you do not, the medicine may not clear up your infection completely. The bacteria could also become less sensitive to this or other medicines. This could make the infection harder to treat in the future.
• Mild diarrhea is common with antibiotic use. However, a more serious form of diarrhea (pseudomembranous colitis) may rarely occur. This may develop while you use the antibiotic or within several months after you stop using it. Contact your doctor right away if stomach pain or cramps, severe diarrhea, or bloody stools occur. Do not treat diarrhea without first checking with your doctor.
• Lab tests, including complete blood cell counts, may be performed while you use Biaxin. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
• Biaxin should not be used in children younger 6 months; safety and effectiveness in these children have not been confirmed.
• Pregnancy and breast-feeding: Biaxin has been shown to cause harm to the fetus. Biaxin is not recommended for use during pregnancy except when no other antibiotics can be used. If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using Biaxin while you are pregnant. It is not known if Biaxin is found in breast milk. If you are or will be breast-feeding while you use Biaxin, check with your doctor. Discuss any possible risks to your baby.

All medicines may cause side effects, but many people have no, or minor, side effects.

Check with your doctor if any of these most common side effects persist or become bothersome:

Abnormal taste; diarrhea; headache; indigestion; nausea; stomach discomfort; vomiting.

Seek medical attention right away if any of these severe side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); bloody stools; confusion; decreased urination; depression; emotional or mood changes; hallucinations; nightmares; severe diarrhea; severe stomach pain/cramps; trouble sleeping.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider.