Lansoprazole/amoxicillin/clarithromycin (By mouth)


Treats H pylori infection and ulcers. This medicine contains a penicillin and a 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

  • Your doctor will tell you how much medicine to use. Do not use more than directed.
  • Swallow the pills 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 together with atazanavir, cisapride, dihydroergotamine, ergotamine, lovastatin, pimozide, or simvastatin.
  • There are many other drugs that can interact with Prevpac®. Make sure your doctor knows about all other medicines you are using. Some of the medicines that can interact include:
    • Alprazolam, carbamazepine, colchicine, digoxin, efavirenz, erlotinib, ketoconazole, itraconazole, methotrexate, midazolam, mycophenolate, nevirapine, probenecid, rifampicin, rifabutin, sildenafil, sucralfate, tacrolimus, tadalafil, theophylline, tolterodine, triazolam, vardenafil, zidovudine
    • Another antibiotic
    • Blood pressure medicine (including amlodipine, diltiazem, verapamil)
    • Blood thinner (including warfarin)
    • Insulin or other diabetes medicine
    • Medicine for heart rhythm problems
    • Statin medicine

Warnings While Using This Medicine

  • Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, heart rhythm problems (such as QT prolongation), lupus, or myasthenia gravis. Tell your doctor if you are allergic to any antibiotic, or have had other problems with taking clarithromycin.
  • This medicine may cause the following problems:
    • Serious liver problems
    • Changes in heart rhythm, such as QT prolongation
    • Kidney 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.
  • Tell any doctor or dentist who treats you that you are using this medicine. This medicine may affect certain medical test results.
  • Call your doctor if your symptoms do not improve or if they get worse.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
  • 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
  • Change in how much or how often you urinate, lower back pain
  • Dark urine or pale stools, loss of appetite, stomach pain, yellow skin or eyes
  • Diarrhea that may contain blood
  • Joint pain, rash on your cheeks or arms that gets worse in the sun
  • Nausea, vomiting, unusual tiredness or weakness, muscle cramps, confusion
  • Fainting, dizziness, lightheadedness
  • Fast, pounding, or uneven heartbeat

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

  • Headache
  • Mild diarrhea, nausea

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 1/27/2017

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