1. Health
You can opt-out at any time. Please refer to our privacy policy for contact information.

Discuss in my forum

Lomotil for Diarrhea


Updated June 17, 2014

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

Doctor writing a prescription.
Photo: Steve Cole/Getty Images

What Is Lomotil?:

Lomotil (diphenoxylate) is a medication used to treat diarrhea. It's an oral medication available in tablet or liquid form. Lomotil is designed for short-term use, as it runs the risk of dependence. In some cases, Lomotil may be prescribed for long-term use under close supervision by a physician.

How Does Lomotil Work?:

Lomotil is made up of two separate ingredients, diphenoxylate and atropine. Diphenoxylate, the primary ingredient in Lomotil, is a narcotic and therefore carries the risk of dependence. Diphenoxlyate works to slow colonic motility, which allows for more liquid to be drawn from the stool, firming it up and thus relieving diarrhea symptoms. A small dose of atropine, an anticholinergic, is included in Lomotil in order to reduce the likelihood of abuse, as higher doses of atropine cause unpleasant physical symptoms.

How to Take:

Before taking Lomotil, make sure that you inform your doctor of any co-existing medical conditions and that they are aware of any other medications that you may be taking. While taking Lomotil:

  • Be sure to follow dosing instructions carefully.
  • Do not drink alcohol.
  • Do not drive or operate machinery, as Lomotil can cause drowsiness.
  • If there is no improvement in your symptoms in two days, call your doctor.
  • The medication may cause dryness in your mouth. Drinking plenty of water and sucking on hard candy may be helpful.

Side Effects:

If you experience any of the following side effects or any other severe, unexpected symptom, call your doctor:

  • Allergic reactions, such as hives or skin rash, or swelling of face, lips or tongue
  • Difficulty breathing
  • Rapid heartbeat or palpitations
  • Severe abdominal pain
  • Vomiting

Is Lomotil Safe for IBS?:

Lomotil appears to be best used as a short-term treatment for diarrhea. Due to risk of dependency, Lomotil should only be used as an ongoing treatment with doctor supervision. As diarrhea-predominant IBS (IBS-D) is a chronic condition, it may be best to pursue alternative treatment options for diarrhea. Finally, it can be dangerous to take Lomotil for bacterial diarrheal infections.

Special Warning:

Children appear to be most at risk for Lomotil overdose. Do not give Lomotil to a child unless directed by your doctor.


"Diphenoxylate and Atropine" PubMed Health Accessed February 8, 2011.

Thomas, T., Pauze, D. & Love, J. "Are One or Two Dangerous? Diphenoxylate-Atropine Exposure in Toddlers" Journal of Emergency Medicine 2008 71-75.


  1. About.com
  2. Health
  3. Irritable Bowel Syndrome (IBS)
  4. Medication
  5. Lomotil for Diarrhea

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.