Amoxicillin is an antibiotic in the penicillin group of drugs. It fights bacteria in your body.

Clarithromycin is in a group of drugs called macrolide antibiotics. Clarithromycin fights bacteria in your body.

Lansoprazole decreases the amount of acid produced in the stomach.

The combination of amoxicillin, clarithromycin, and lansoprazole is used to prevent stomach ulcer caused by infection with Helicobacter pylori (H. pylori).

Amoxicillin, clarithromycin, and lansoprazole may also be used for other purposes not listed in this medication guide.

You should not take this medication if you are allergic to amoxicillin (Amoxil, Trimox, Dispermox), clarithromycin (Biaxin), lansoprazole (Prevacid), or to certain other antibiotics.

While you are taking amoxicillin, clarithromycin, and lansoprazole, do not take any of the following medications: cisapride (Propulsid), ergotamine (Ergomar, Cafergot, Ercaf, Migergot), dihydroergotamine (D.H.E. 45, Migranal Nasal Spray), ergonovine (Ergotrate), or pimozide (Orap).

Tell your doctor if you have kidney or liver disease, myasthenia gravis, or if you are allergic to any drugs (especially any antibiotics).

Amoxicillin can make birth control pills less effective, which may result in pregnancy. Before taking amoxicillin, clarithromycin, and lansoprazole, tell your doctor if you use birth control pills.

There are many other medicines that can interact with amoxicillin, clarithromycin, and lansoprazole. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a new medication without telling your doctor.

You should not take this medication if you are allergic to amoxicillin (Amoxil, Trimox, Dispermox), clarithromycin (Biaxin), lansoprazole (Prevacid), or to any of the following antibiotics:

• ampicillin (Omnipen, Principen);

• azithromycin (Zithromax);

• carbenicillin (Geocillin);

• dicloxacillin (Dycill, Dynapen);

• erythromycin (E.E.S., EryPed, Ery-Tab, Erythrocin);

• oxacillin (Bactocill);

• penicillin (Beepen-VK, Ledercillin VK, Pen-V, Pen-Vee K, Pfizerpen, V-Cillin K, Veetids, and others);

• telithromycin (Ketek); or

• troleandomycin (Tao).

Taking any of the following medicines together with amoxicillin, clarithromycin, and lansoprazole can cause a life-threatening side effect on your heart:

• cisapride (Propulsid);

• ergotamine (Ergomar, Cafergot, Ercaf, Migergot);

• dihydroergotamine (D.H.E. 45, Migranal Nasal Spray), ergonovine (Ergotrate); or

• pimozide (Orap).

If you have certain conditions, you may need a dose adjustment or special tests to safely use this medication. Before taking amoxicillin, clarithromycin, and lansoprazole, tell your doctor if you have:

• kidney disease;

• liver disease;

• myasthenia gravis; or

• if you are allergic to any drugs (especially an antibiotic).

FDA pregnancy category C. Clarithromycin may be harmful to an unborn baby. Before taking this medication, tell your doctor if you are pregnant or plan to become pregnant during treatment.

Amoxicillin can make birth control pills less effective, which may result in pregnancy. Before taking amoxicillin, clarithromycin, and lansoprazole, tell your doctor if you use birth control pills.

Amoxicillin, clarithromycin, and lansoprazole can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.