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Pepto-Bismol

Generic name: bismuth subsalicylate

Brand names: Bismarex, Bismatrol, Bismatrol Maximum Strength, Kaopectate, Kola-Pectin DS, Peptic Relief, Pepto-Bismol, Percy Medicine, Pink Bismuth, Soothe Caplets

Last updated November 12, 2025 0 views Reviewed by Melisa Puckey, BPharm
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What is Pepto-Bismol?

Pepto-Bismol is used to treat diarrhea, travelers' diarrhea, nausea, heartburn, indigestion, gas, or upset stomach.

Pepto-Bismol works as an antacid to reduce excess stomach acid and so eases discomfort. It also works to protect the stomach and lower part of your food pipe (esophagus) from stomach acid.

Pepto-Bismol can be taken as a tablet or liquid, depending on which one you prefer.

How should I take Pepto-Bismol?

Take this medicine exactly as directed on the label, or as prescribed by your doctor.

Shake the oral suspension (liquid) before you measure a dose. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

You must chew the chewable tablet before you swallow it.

Drink plenty of liquids while you are taking this medicine.

Taking more than the recommended dose will not make this medicine more effective, and may cause serious side effects.

Call your doctor if you still have diarrhea after 2 days of using this medicine.

This medicine can affect the results of certain medical tests. Tell any doctor who treats you that you are using bismuth subsalicylate.

Store at room temperature away from moisture and heat. Do not freeze.

Warnings

You should not use Pepto-Bismol if you have bleeding problems, blood in your stools, or if you are allergic to aspirin or other salicylates.

You should not use Pepto-Bismol for a stomach ulcer unless your ulcer is caused by H. pylori and your doctor has prescribed Pepto-Bismol as part of modified bismuth-containing quadruple therapy (mBCQT).

Using this medicine in a child or teenager with flu symptoms or chickenpox can cause a serious or fatal condition called Reye's syndrome.

Before taking this medicine

You should not use Pepto-Bismol if you are allergic to bismuth subsalicylate, or if you have:

  • black or bloody stools;
  • a stomach ulcer (unless your doctor has prescribed Pepto-Bismol as part of modified bismuth-containing quadruple therapy);
  • bleeding problems; or
  • if you are allergic to salicylates such as aspirin, Doan's Extra Strength, Salflex, Tricosal, and others.

Using this medicine in a child or teenager with flu symptoms or chickenpox can cause a serious or fatal condition called Reye's syndrome.

Ask a doctor or pharmacist if this medicine is safe to use if you have or have ever had:

  • mucus in your stools; or
  • if you currently have a fever.

Ask a doctor before using this medicine if you are pregnant or breastfeeding.

Do not give this medicine to a child younger than 12 years old without medical advice.

Pepto-Bismol may contain phenylalanine and could be harmful if you have phenylketonuria (PKU).

Pepto-Bismol side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop taking this medicine and call your doctor at once if you have:

  • changes in behavior with nausea and vomiting;
  • hearing loss or ringing in your ears;
  • diarrhea lasting longer than 2 days; or
  • worsened stomach symptoms.

Bismuth subsalicylate may cause you to have a black or darkened tongue. This is a harmless side effect.

Common Pepto-Bismol side effects include:

  • constipation; or
  • dark colored stools.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What happens if I miss a dose?

Since bismuth subsalicylate is used when needed. If you are on a dosing schedule, skip any missed dose. Do not use two doses at one time.

Do not take more than 8 doses per day.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include weakness, depression, anxiety, feeling irritable, problems with balance or coordination, confusion, tremors, or jerky muscle movements.

Ask a doctor or pharmacist before taking other antacids, diarrhea medicine, or taking medicine that may contain a salicylate (such as aspirin, salsalate, magnesium salicylate, choline salicylate, diflunisal, Ecotrin, Tricosal, Trilisate, and others).

What other drugs will affect Pepto-Bismol?

Ask a doctor or pharmacist before using bismuth subsalicylate with any other medications, especially:

  • arthritis medicine;
  • gout medicine;
  • insulin or oral diabetes medications; or
  • a blood thinner--warfarin, Coumadin, Jantoven.

This list is not complete. Other drugs may affect Pepto-Bismol, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Common questions about Pepto-Bismol

Can you give Pepto Bismol to kids?
Several formulations of Pepto-Bismol can be used in children. The original strength of Pepto-Bismol liquid (“the pink stuff” or “Pepto”) can be given to children 12 years and older. Kids from 2 to 12 years can take Pepto Kids, a chewable, bubblegum-flavored tablet that contains the antacid calcium carbonate. Continue reading
What is the fastest way to stop diarrhea?
Over-the-counter medication like loperamide (Imodium) or bismuth subsalicylate (Pepto-Bismol) can help stop diarrhea quickly, but always consult with a healthcare professional. Continue reading
How long does it take for Pepto Bismol to work?
Pepto-Bismol is an over-the-counter medication that usually works within 30 to 60 minutes. It can be used to treat diarrhea and upset stomach in people 12 years and older. Continue reading
Why does Pepto-Bismol turn your tongue black?
Pepto-Bismol can turn your tongue black because its active ingredient, bismuth subsalicylate, contains bismuth. When bismuth mixes with small amounts of sulfur in your saliva, it forms bismuth sulfide, a black substance that stains the surface of your tongue. This side effect is temporary and harmless. Continue reading
Does Pepto-Bismol help with diarrhea?
Pepto-Bismol is an over-the-counter (OTC) medicine that can be used to treat diarrhea and traveler's diarrhea in adults and children 12 years and older. For diarrhea, it’s available as an oral liquid, liquicap, or caplet. It typically takes 30 to 60 minutes to start working, but you may need several doses. Continue reading
What causes black hairy tongue?
Black hairy tongue is often caused by an overgrowth of papillae (taste buds) on the tongue. It results in a dark, furry appearance of dead skin cells on the surface of the tongue that can be stained from bacteria, food, or tobacco. Although it may be unpleasant, it doesn't usually require medical treatment and it's temporary and harmless. Continue reading

Related medicines

Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
General medicine information Consumer-friendly language Source: Drugs.com

Content is provided for education and is not medical advice. See our medical disclaimer. Source page medically reviewed by Melisa Puckey, BPharm on November 12, 2025.