Loperamide (loperamide hydrochloride -HCI)

What is loperamide?

Loperamide is an antidiarrheal active ingredient available in over-the-counter (OTC) medicines that treat the symptoms of diarrhea, including traveler’s diarrhea. Loperamide can be the only active ingredient in an anti-diarrheal medicine or it can be found in medicines that also treat symptoms such as gas.

What is loperamide used to treat?

  • Diarrhea
  • Traveler’s diarrhea
Common brands containing loperamide:
  • Imodium
  • Store Brands (ex. Walmart’s “Equate” store brand or CVS Health store brand)

How much loperamide can you take?

Different types of products containing this active ingredient have different strengths. That’s why it is always important to read and follow the Drug Facts label. Most medicines warn against use of an active ingredient for longer than 7-10 days. Stop use and ask a doctor if symptoms persist.

Safety guide for loperamide

Loperamide is approved by the U.S. Food and Drug Administration (FDA) and is safe and effective when used according to the Drug Facts label. Do not exceed the maximum daily dose (8 mg per day for adults).

Ask a healthcare provider before use if:

  • You are taking an antibiotic, antifungal, histamine 2 receptor antagonist, HIV medication or gemfibrozil (a cholesterol lowering drug).
  • You have a fever.
  • You have mucus in your stool.
  • You have a history of liver disease.
  • You are pregnant or breastfeeding.
  • You are taking other prescription and OTC medicines, vitamins, and other dietary supplements.
  • Talk to a healthcare provider before giving an OTC containing loperamide to a child under the age of 6.

Do not use if:

  • You have ever had a rash or other allergic reaction to loperamide.
  • You have bloody or black stool.
  • Talk to a healthcare professional prior to use in children under the age of 6.

Stop use and ask a doctor if:

  • Your symptoms get worse.
  • Your diarrhea lasts for more than two days.
  • Seek immediate medical attention if you experience any of the following: fainting; rapid heartbeat or irregular heart rhythm.
  • You get abdominal swelling or bulging.
  • You take too much. Immediately contact a healthcare provider or the poison control national helpline at 800.222.1222.

What are the side effects of loperamide?

  • Taking higher than recommended doses of loperamide (maximum OTC dose is 8 mg per day for adults), including through abuse or misuse of the product, can cause serious heart problems that can lead to death.
  • The risk of serious heart problems may also be increased when high doses of loperamide are taken with medicines that interact with loperamide (see the FDA list of drugs that can potentially interact with loperamide here).
  • When using medicines containing loperamide, tiredness, drowsiness, or dizziness may occur.
  • You should use care when driving or operating machinery.