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Lansoprazole

Brand names: Prevacid, Prevacid 24HR, Prevacid SoluTab

Lansoprazole is a proton pump inhibitor (PPI) that lowers stomach acid to treat heartburn, reflux, and ulcers.

Brand namesPrevacid, Prevacid 24HR, Prevacid SoluTab
Type of medicineProton pump inhibitor (acid reducer)
Prescription?Both prescription and over the counter
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

Dissolving tablets are handy for children and people who can't swallow capsules.

What it's used for

  • Frequent heartburn and GERD
  • Ulcers
  • Part of H. pylori treatment

How to take it

  • Take it before a meal, usually breakfast.
  • Swallow capsules whole, or open and sprinkle on applesauce if your label allows.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Diarrhea
  • Stomach pain
  • Nausea
  • Headache
Call your provider todaySevere watery diarrhea that won't stop (possible C. diff)
Call your provider todayMuscle cramps, shakiness, or a jumpy heartbeat (possible low magnesium)
Call your provider todayPeeing less, or a rash with joint pain

Warnings

  • Long-term use is linked to low magnesium and B12 and bone fractures.
  • See a provider for trouble swallowing, vomiting blood, black stools, or weight loss.

Other medicines, foods, and alcohol

  • It can change methotrexate and some HIV medicine levels.
  • It lowers absorption of some medicines that need stomach acid.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Talk with your provider.

Missed doses, overdose, and storage

If you miss a dose

Take it as soon as you remember, unless it's almost time for your next dose. Then skip the missed dose. Don't take two doses at once.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.