Prescription or OTCLower-cost generic available



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Treats heartburn and stomach ulcers.

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Prescription or OTCLower-cost generic available

Our bottom line

Prevacid (Lansoprazole) gives you long-lasting heartburn relief and helps heal ulcers.


  • Most people can take Prevacid (Lansoprazole) without any noticeable day-to-day side effects.
  • Prevacid (Lansoprazole) lasts longer than other types of antacids (like Zantac, Pepcid, or Tums), and you only need to take it once or twice a day.
  • You can take it in combination with a quick-acting antacid (like Maalox or Tums) if you need relief right away.
  • Available as both a generic and over-the-counter option, so it's pretty affordable.
  • Sometimes if one PPI doesn't work, another medication in the same class will work for you.


  • Doesn't start working as fast as some other antacids like Tums, Rolaids, or Maalox.
  • Depending on the condition you are treating, it can take one to two weeks to get the full effect.
  • If you are taking Prevacid (Lansoprazole) for a long time you should take a calcium supplement to prevent fragile bones.
  • Can interact with other drugs, so be sure your doctor knows all the medicine you're taking before starting Prevacid (Lansoprazole).

Save on your next Prevacid (Lansoprazole) prescription

Get the lowest price for your medication, even if you have insurance.

What to expect when you take Prevacid (Lansoprazole) for Ulcer

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Tips from our pharmacists
  • Take Prevacid (Lansoprazole) about 1 hour before a meal.
  • Don't chew or crush capsules, but swallow them whole.
  • If you have trouble swallowing, there's a tablet available that dissolves in your mouth.
  • Give Prevacid (Lansoprazole) a chance to work. You'll see some benefits right away, but the full effects can take a week or so to kick in.
  • Avoid drug interactions by telling your doctor all of the other medications or herbal supplements you take before starting Prevacid (Lansoprazole).
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Side effects for Prevacid (Lansoprazole)

From clinical trials of Prevacid / Stomach ulcer prevention  ( 3795)

  • DiarrheaDiarrhea4% for Prevacid vs.2% for placebo
  • Abdominal painAbdominal pain2% for Prevacid vs.1% for placebo
  • ConstipationConstipation1% for Prevacid vs.0% for placebo
  • NauseaNausea1% for Prevacid vs.1% for placebo

Risks and Warnings for Prevacid (Lansoprazole)

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  • Heartburn and feelings of upset stomach can be warning signs of a more serious stomach problem or cancer. If you need to take Prevacid (Lansoprazole) for 2 weeks or more go see a doctor. It's safest to get checked out to make sure you do not have a serious stomach condition.

Means that some groups have a high risk of experiencing this side effect

Tips from pharmacists and people taking Prevacid (Lansoprazole)

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The FDA category for this medication is B. It is advised that you: Probably safe
  • Tips from our pharmacists
  • Take Prevacid (Lansoprazole) about 1 hour before a meal.
  • take 2 times a day, once before breakfast and once before dinner
  • take 2 times a day half hour before meals