bismuth subsalicylate (Pepto Bismol, Kaopectate, Bismatrol Maximum Strength, and others) (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

The antidiarrheal benefits of bismuth subsalicylate may be due to the reduction in prostaglandin synthesis. Bismuth subsalicylate also prevents the attachment of bacteria to the walls of the intestine, inactivates enterotoxins (toxic chemicals made by bacteria), and has a direct inhibiting effect on bacteria.

Bismuth subsalicylate was first approved by the FDA in 1939.

PRESCRIBED FOR: Bismuth subsalicylate is used for over-the-counter (OTC):

  • treatment of nonspecific diarrhea,
  • prevention of traveler's diarrhea,
  • part of a multidrug regimen to eradicate H. pylori, and
  • for over-the-counter treatment of:
    • upset stomach,
    • heartburn,
    • indigestion, and
    • nausea.

SIDE EFFECTS: Dark brown or black stools are common with use of bismuth subsalicylate. Tongue discoloration and constipation also may occur.

Other side effects associated with bismuth subsalicylate include:




  • Chewable tablets: 262, 525 mg
  • Oral suspension: 262 mg/15 ml, maximum strength 525 mg/15 ml
  • Caplets: 262 mg
Medically Reviewed by a Doctor on 5/12/2015

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