Lansoprazole/amoxicillin/clarithromycin (By mouth)


Treats H pylori. This medicine contains a penicillin and macrolide antibiotic.

Brand Name(s)

Prevpac, Triple Therapy

When This Medicine Should Not Be Used

How to Use This Medicine

Capsule, Tablet, Delayed Release Capsule

  • Take your medicine as directed.
  • Capsule or tablet: Swallow whole. Do not chew, crush, or break any of them.
  • It is best to take this medicine on an empty stomach, before a meal.
  • Take all of the medicine in your prescription to clear up your infection, even if you feel better after the first few doses.
  • Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Do not use this medicine if you are also using atazanavir, cisapride, pimozide, ergotamine, dihydroergotamine, lovastatin, or simvastatin.
  • Some medicines and foods can affect how this drug works. Tell your doctor if you are also using colchicine, methotrexate, digoxin, iron, ketoconazole, itraconazole, sucralfate, carbamazepine, theophylline, rifampicin, rifabutin, rifapentine, sildenafil, tadalafil, vardenafil, or tolterodine.
  • Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol.
  • Tell your doctor if you use any of the following:
    • Diabetes medicine
    • Blood thinner (such warfarin)
    • Another antibiotic, including a sulfa drug
    • Proton pump inhibitor
    • Medicine for heart rhythm problems
    • Sedative or anxiety medicine
    • Blood pressure medicine
    • Statin medicine
    • Medicine to treat HIV/AIDS

Warnings While Using This Medicine

  • Tell your doctor if you are pregnant or breastfeeding, or if you have diabetes, kidney or liver disease, or heart rhythm problems. Tell your doctor if you are allergic to any antibiotic.
  • This medicine may cause the following problems:
    • Liver problems
    • Heart rhythm problems
  • This medicine can cause diarrhea. Call your doctor if the diarrhea becomes severe, does not stop, or is bloody. Do not take any medicine to stop diarrhea until you have talked to your doctor. Diarrhea can occur 2 months or more after you stop taking this medicine.
  • Call your doctor if your symptoms do not improve or if they get worse.
  • Tell any doctor or dentist who treats you that you are using this medicine. This medicine may affect certain medical test results.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Blistering, peeling, red skin rash
  • Dark urine or pale stools, nausea, vomiting, loss of appetite, stomach pain, yellow skin or eyes
  • Diarrhea that may contain blood
  • Fast or irregular heartbeat
  • Unusual tiredness or weakness, muscle cramps, confusion

If you notice these less serious side effects, talk with your doctor:

  • Bad taste in your mouth
  • Change in the color of your teeth or tongue
  • Headache or stomach pain
  • Nausea
  • Vaginal itching or discharge

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Version Info

  • Last reviewed on 7/4/2015

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