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Pepto Diarrhea Control Side Effects

Generic Name: loperamide

Note: This document contains side effect information about loperamide. Some of the dosage forms listed on this page may not apply to the brand name Pepto Diarrhea Control.

For the Consumer

Applies to loperamide: oral capsule, oral capsule liquid filled, oral liquid, oral solution, oral suspension, oral tablet, oral tablet chewable

Along with its needed effects, loperamide (the active ingredient contained in Pepto Diarrhea Control) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking loperamide:


Check with your doctor as soon as possible if any of the following side effects occur while taking loperamide:


Some side effects of loperamide may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:


For Healthcare Professionals

Applies to loperamide: compounding powder, oral capsule, oral liquid, oral suspension, oral tablet, oral tablet chewable


The most common adverse events were constipation, flatulence, headache, nausea, and dizziness.


Common (1% to 10%): Constipation, nausea, flatulence, dry mouth, abdominal cramp, colic, vomiting, meteorism, abdominal pain
Uncommon (0.1% to 1%): Abdominal discomfort, abdominal pain upper, dyspepsia
Rare (less than 0.1%): Ileus (including paralytic ileus), megacolon (including toxic megacolon), abdominal distension[Ref]

Nervous system

Common (1% to 10%): Headache, dizziness
Uncommon (0.1% to 1%): Somnolence
Rare (less than 0.1%): Loss of consciousness, stupor, depressed level of consciousness, hypertonia, coordination abnormality
Postmarketing reports: Syncope[Ref]


Rare (less than 0.1%): Fatigue
Postmarketing reports: Death, tiredness[Ref]


Rare (less than 0.1%): Hypersensitivity reaction, anaphylactic reaction (including anaphylactic shock), anaphylactoid reaction[Ref]


Postmarketing reports: QT/QTc prolongation, Torsades de Pointes, other ventricular arrhythmias, cardiac arrest[Ref]


Uncommon (0.1% to 1%): Rash
Rare (less than 0.1%): Bullous eruption (including Stevens-Johnson syndrome, toxic epidermal necrolysis, and erythema multiforme), angioedema, urticaria, pruritus[Ref]


Rare (less than 0.1%): Urinary retention[Ref]


Rare (less than 0.1%): Miosis


1. "Product Information. Loperamide Hydrochloride (loperamide)." Teva Pharmaceuticals USA, North Wales, PA.

2. Walley T, Milson D "Loperamide related toxic megacolon in Clostridium difficile colitis." Postgrad Med J 66 (1990): 582

3. "Product Information. Imodium (loperamide)." Janssen Pharmaceutica, Titusville, NJ.

4. Brown JW "Toxic megacolon associated with loperamide therapy." JAMA 241 (1979): 501-2

5. Ericsson CD, Johnson PC "Safety and efficacy of loperamide." Am J Med 88 (1990): s10-4

6. Olm M, Gonzalez FJ, Garcia-Valdecasas JC, Fuster J, Bertran A, Milla J "Necrotising colitis with perforation in diarrhoic patients treated with loperamide." Eur J Clin Pharmacol 40 (1991): 415-6

7. Katz JP, Sturmann KM "Appendicitis associated with loperamide hydrochloride abuse." Ann Pharmacother 27 (1993): 369-70

8. Hill MA, Greason FC "Loperamide dependence." J Clin Psychiatry 53 (1992): 450

Some side effects of Pepto Diarrhea Control may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.