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What is Pepto Bismol?

Pepto Bismol is a brand of over-the-counter (OTC) medications used to treat digestive symptoms, such as nausea, heartburn, indigestion, and diarrhea.¹

Known for its bright pink color and its catchy jingle, Pepto Bismol is an immediately recognizable item in many household medicine cabinets.

Its active ingredient is an antacid and antidiarrheal agent called bismuth subsalicylate.

Both bismuth and subsalicylate reduce inflammation in the gastrointestinal (GI) tract and provide relief from uncomfortable symptoms. Bismuth is also known to have antimicrobial effects, preventing the growth of pathogenic bacteria in the stomach.²

What is Pepto Bismol used to treat?

The US Food and Drug Administration (FDA) approved Pepto Bismol for the treatment of the following five symptoms:³

  • Nausea

  • Heartburn

  • Indigestion

  • Upset stomach

  • Diarrhea

Many people reach for Pepto Bismol to remedy the discomfort caused by consuming heavy meals.

Pepto Bismol also has off-label uses as part of a regimen for treating Helicobacter pylori infection and to prevent traveler’s diarrhea. An off-label use is not approved by the FDA.⁴

Dosage forms and strengths

Pepto Bismol is available over the counter in a variety of formulations, including chewable tablets, caplets, liquicaps, and a liquid suspension.⁵

The chewable tablets, caplets, and liquicaps contain 262mg of bismuth subsalicylate per tablet.

The liquid suspension contains 525mg per 30mL dose.

Below, you’ll find specific usage instructions for Pepto Bismol’s most popular original formula products.

Pepto Bismol (original liquid)

Active ingredient: Bismuth subsalicylate 525mg/30mL

Before use: Shake well and only use the dosing cup provided with the packaging.

Dosage instructions: Adults and children aged 12 years and older may take 30mL every 30 minutes or 60mL every hour as needed. Do not take more than 240mL (4,200mg) in a 24-hour period. Discontinue use if symptoms persist after two days.

Pepto Bismol (chewable tablets)

Active ingredient: Bismuth subsalicylate 262mg per chewable tablet

Dosage instructions: Adults and children aged 12 years and older may take two chewable tablets every 30 minutes or four chewable tablets every hour as needed. The maximum dose is 16 chewable tablets (4,102mg) in 24 hours for up to two days. 

Pepto Bismol (caplets, liquicaps)

Active ingredient: Bismuth subsalicylate 262mg per caplet

Dosage instructions: Take with water. Adults and children aged 12 years and older may take two caplets every 30 minutes or four caplets every hour as needed. Do not take more than 16 caplets (4,102mg) in 24 hours. Discontinue use if symptoms persist for longer than 48 hours.

How do you take Pepto Bismol?

Pepto Bismol should be taken as directed on the package or by your doctor.

Chewable tablets should be chewed thoroughly before swallowing.

The liquid suspension should be shaken first and then measured into the dosing cup provided.

The tablets and caplets should be taken with a full glass of water.

The maximum dose of 16 tablets or caplets or 240mL (approximately 4,200mg) in 24 hours should not be exceeded.

Discontinue use if your symptoms have not subsided in two days. Contact your primary physician or seek medical help if your symptoms do not improve, if they worsen, or if you develop fever, dehydration, or any other new symptoms.

Seeing results

The effects of Pepto Bismol on stomach discomfort are usually felt within 30–60 minutes of taking the medication and can last for up to four hours. The medication generally controls diarrhea within 24 hours.⁶ ⁷

Speak with your doctor if your symptoms persist after using this medication for two days.

Who should not take Pepto Bismol?

Pepto Bismol should be taken with caution — or not taken at all — by people with any of the following:⁸

  • Under 12 years of age

  • Known allergy to bismuth subsalicylate or salicylates (like aspirin)

  • Allergy to any of the inactive ingredients in this medication, particularly the following red dyes:

    • D&C Red #22 and #28 (in the liquid form)⁹

    • D&C Red #40 (in the chewable tablet)¹⁰

    • D&C Red #27 (in the regular tablet)¹¹

  • Pregnant or breastfeeding¹²

  • Gout

  • Kidney or liver disease

  • Taking other salicylate products as this may cause salicylate toxicity (see below for details regarding salicylate toxicity and overdose)

  • Children recovering from chickenpox or the flu (due to the risk of Reye’s syndrome)¹³

  • Bleeding disorder, such as hemophilia, or taking anticoagulant medications

  • Peptic ulcer disease or a history of bloody or black stools

  • G6PD deficiency

  • Recent live varicella or nasal influenza vaccine (within the past six weeks)

Potential side effects of Pepto Bismol

Common side effects

One of the most common side effects of taking Pepto Bismol is a blackening of the tongue and feces. This harmless side effect occurs when the active ingredient interacts with sulfur that is naturally present in your body. It resolves a few days after you stop taking the medication.¹⁴

Some other common side effects of taking Pepto Bismol include the following:¹⁵

  • Constipation

  • Heartburn

  • Dizziness

  • Headache

  • Loss of appetite

  • Nausea, vomiting

  • Headache

Severe adverse effects

Like other medications, there have been some severe side effects reported after taking Pepto Bismol. These effects, though rare, can be life-threatening.

Severe adverse effects of this medication include any of the following:¹⁶

  • Increased heart rate

  • Ringing or buzzing sounds in the ears

  • Psychosis, confusion, delirium

  • Involuntary muscle spasm or twitching

  • Seizures

If you notice any of these symptoms after taking Pepto Bismol, contact your doctor immediately. 

Reye’s syndrome

The most serious potential side effect associated with Pepto Bismol is a rare condition known as Reye’s syndrome. Children and teenagers recovering from chickenpox may be susceptible to this complication. It is precipitated by salicylates (aspirin-derived compounds) like those found in Pepto Bismol.¹⁷

Symptoms of Reye’s syndrome include nausea and vomiting and behavioral changes like confusion, seizures, and loss of consciousness.¹⁸

This metabolic disorder can be life-threatening, involving liver failure and inflammation of the brain.


It’s possible to overdose on Pepto Bismol.

Symptoms of a mild overdose include vomiting, confusion, fever, ringing in the ears, and abdominal pain.¹⁹

The toxic effects of an overdose are due to salicylate toxicity, which can cause very severe adverse effects such as:

  • Confusion

  • Slurred speech

  • Hallucinations

  • Rapid heart rate

  • Abnormal heart rhythms

  • Tremors

  • Seizures

  • Loss of consciousness

  • Respiratory failure

If you or someone you know has taken an overdose of Pepto Bismol, seek medical attention immediately. 

Allergy information

Anyone with a known allergy to bismuth subsalicylate or any of the inactive ingredients in this medication should not take Pepto Bismol.

Also avoid taking Pepto Bismol if you have a known allergy to salicylates like aspirin.

Symptoms of an allergic reaction can include any of the following:

  • Rash, hives, itching, peeling skin

  • Vomiting

  • Swelling of the face, lips, and tongue causing difficulty swallowing

  • Respiratory distress, wheezing

  • Loss of consciousness

Long-term use of Pepto Bismol

Pepto Bismol is not meant for long-term, chronic use. Taking it for a prolonged period may increase your risk of experiencing side effects.²⁰

Additionally, bismuth encephalopathy can occur in rare cases, leading to complications, such as seizures, loss of coordination, movement disorder, involuntary twitching, and other neurological signs, all of which are reversible.²¹

If you find yourself taking Pepto Bismol repeatedly for chronic GI symptoms, it’s best to discuss potential long-term treatment options with your doctor.

Pregnancy category

Pepto Bismol has been designated a pregnancy risk category C drug by the FDA.²²

A category C rating means there have been insufficient studies of the drug in human subjects, and testing in animals demonstrated some fetal risks.²³

Pepto Bismol and pregnancy

Before 20 weeks gestation, your doctor will weigh the potential risks of taking this medication against the known benefits.

Pepto Bismol should not be taken after 20 weeks gestation. While there is insufficient human research to confirm the safety of use during pregnancy, there is a risk of kidney dysfunction and oligohydramnios (insufficient amniotic fluid) from 20 weeks gestation.

From 30 weeks gestation, there is a risk of premature fetal ductus arteriosus closure.

Pepto Bismol and breastfeeding

Women who are breastfeeding should avoid taking this medication as it may be passed through breast milk and cause harm to the infant. There is no human data to support possible side effects of breastfeeding while taking Pepto Bismol, but toxicity is possible.²⁴

Missed doses

Taking a dose of Pepto Bismol every 30–60 minutes is recommended until your symptoms are relieved. Do not exceed a maximum of eight doses in a 24-hour period.²⁵

Pepto Bismol is taken on an as-needed basis. If you miss the timing for your next dose, you can take it as soon as you remember.

Be sure to check with your doctor for individualized dosing instructions.

Drug interactions

Even though it can be purchased over the counter, Pepto Bismol can interact with other medications.

Drugs known to have interactions with Pepto Bismol include the following:²⁶

  • Aspirin or aspirin-like drugs, including non-steroidal anti-inflammatory drugs (NSAIDs) like meloxicam (Mobic), ibuprofen (Motrin, Advil), and naproxen (Naprosyn)

  • Antibiotics, such as doxycycline (Doryx), minocycline, and tetracycline

  • Diuretics, such as acetazolamide, methazolamide, and spironolactone

  • Gout medicines like allopurinol (Zyloprim), probenecid (Probalan), and pegloticase (Krystexxa)

  • Dichlorphenamide (Keveyis)

  • Blood thinners, such as warfarin (Coumadin, Jantoven)

  • Medications for attention-deficit/hyperactivity disorder (ADHD) like atomoxetine (Strattera) and amphetamine (Adderall, Concerta)

  • Steroids like dexamethasone (Decadron and others) and prednisone (Rayos and others)

  • Methotrexate

  • Anti-seizure medicines, such as topiramate (Topamax) and zonisamide (Zonagran)

  • Minoxidil (Rogaine)

  • Decongestants like phenylephrine (Neo-Synephrine) and oxymetazoline (Afrin, Vicks Sinex)

  • Diabetes medications, such as ertugliflozin (Steglatro)

  • Alcohol and cocaine

This is not a complete list of drugs that can interact with Pepto Bismol. It’s best to review all your medications with your doctor before taking the drug.

Can I drink alcohol while taking Pepto Bismol?

It’s not recommended to drink alcohol while taking Pepto Bismol as it may reduce its action in the body.²⁷

If you choose to drink alcohol while using this medication, it’s important to do so in moderation and speak with your doctor beforehand.

What to discuss with your doctor before taking Pepto Bismol

Before taking Pepto Bismol, discuss with your doctor any of the following that apply to you:

  • All medications you are currently taking or take occasionally, including prescription and OTC drugs, supplements, and herbal preparations

  • Any medication allergies, particularly if you’ve had an allergic reaction to aspirin, NSAIDs, or red dyes

  • Current and past health problems, such as kidney or liver disease, gout, a bleeding or clotting disorder, history of GI bleeding, and glucose-6-phosphate dehydrogenase (G6PD) deficiency

  • Pregnancy or planning a pregnancy

  • Vaccination with a live nasal influenza or varicella vaccine within the past six weeks

Additionally, tell your doctor if you are planning to visit countries in which malaria is prevalent. Pepto Bismol may decrease the effectiveness of medications prescribed for malaria prevention.²⁸

Stopping Pepto Bismol

Pepto Bismol should be taken as needed according to the label or your doctor’s directions. Don’t take Pepto Bismol for more than two days.

Immediately stopping the drug will not cause any side effects.

Drug approval history

Originally created to cure a cholera outbreak in the early 20th century, Pepto Bismol quickly became a household name. When the medication was formulated over 100 years ago, handwashing and other cholera-prevention measures weren’t as well-established or practiced as they are today.²⁹

The FDA officially approved bismuth subsalicylate in 1939 for treating diarrhea, heartburn, indigestion, nausea, and mild upset stomach. It is one of the most widely used and recognizable OTC medications for digestive symptoms.³⁰

Tips for taking Pepto Bismol

  • Take as directed on the package or by your pharmacist or doctor.

  • Chew the chewable tablets thoroughly before swallowing.

  • Take liquid suspension doses with a full glass of water. Use the measurement device provided (usually the cap) for measuring out your dose, not a household spoon or measuring spoon.

  • Do not take more than eight doses in 24 hours.

  • Speak with your doctor before taking this medication if you are pregnant, breastfeeding, have any pre-existing medical conditions, or take any medications that might interact with Pepto Bismol.

  • Avoid alcohol while taking Pepto Bismol as it may reduce how well it works in the body and increase the risk of side effects.

Frequently asked questions

Why is Pepto Bismol pink?

According to a sound bite from Procter & Gamble spokesman Jim Schwartz, “Somebody who helped develop it suggested the color because he thought kids would like it.”³¹

As for what ingredients give the well-known medicine its bright hue, the answer lies in artificial dyes, which you’ll find directly on the label.

Can I give Pepto Bismol to my children?

The original formula is designated for adults and children over 12 because there are insufficient studies confirming the safety of Pepto Bismol in younger children.³²

However, Pepto Kids is a different formula offered by the Pepto Bismol company that is approved for children aged 2–11 years. It does not contain bismuth or salicylate.³³

Should Pepto Bismol be refrigerated?

Pepto Bismol does not need to be refrigerated. According to the manufacturer, you should not freeze the product or expose it to temperatures above 104°F (40°C).

Can I take Pepto Bismol with food?

The manufacturer states that Pepto Bismol can be taken with or without food.

Can I take Pepto Bismol if I have chronic GI problems?

It’s best to consult with your doctor if you have ongoing GI issues. Pepto Bismol may not be addressing your underlying condition and should not be taken for more than two days at a time.

  1. Pepto Bismol | Pepto Bismol

  2. Bismuth subsalicylate: Uses, Interactions, Mechanism of Action | DrugBank Online

  3. bismuth subsalicylate (OTC) — Dosing & Uses | reference Medscape

  4. Bismuth Subsalicylate | NIH: StatPearls

  5. All Pepto Bismol Products | Pepto Bismol

  6. Common questions about Pepto-Bismol | NHS

  7. Bismuth Subsalicylate - an overview | ScienceDirect

  8. Pepto-Bismol: Dosing, contraindications, side effects, and pill pictures | epocrates online

  9. Label: PEPTO-BISMOL- bismuth subsalicylate suspension (2023) | NIH: DailyMed

  10. PEPTO-BISMOL- bismuth subsalicylate tablet (2023) | NIH: DailyMed

  11. Label: PEPTO-BISMOL- bismuth subsalicylate tablet (2023) | NIH: DailyMed

  12. Over-the-Counter Medications in Pregnancy (2014)

  13. Pepto-Bismol Original Chewables 5 Symptom Medicine - Including Upset Stomach & Diarrhea Relief 12 Count | smartlabel

  14. Bismuth Subsalicylate - an overview | ScienceDirect

  15. bismuth subsalicylate (OTC) — Adverse Effects | reference Medscape

  16. Bismuth subsalicylate toxicity as a cause of prolonged encephalopathy with myoclonus (1995)

  17. Label: PEPTO-BISMOL- bismuth subsalicylate tablet (2023) | NIH: DailyMed

  18. Reye’s Syndrome | NIH: National Institute of Neurological Disorders and Stroke

  19. Salicylates Toxicity | NIH: StatPearls

  20. How and when to take Pepto-Bismol | NHS

  21. Bismuth encephalopathy- a rare complication of long-standing use of bismuth subsalicylate (2019)

  22. Over-the-Counter Medications in Pregnancy (2014)

  23. Pregnancy Medications | NIH: Statpearls

  24. Bismuth Subsalicylate | NIH: Drugs and Lactation Database (LactMed®)

  25. When & How to Take Pepto Bismol? | Pepto Bismol

  26. Pepto-Bismol: Dosing, contraindications, side effects, and pill pictures | epocrates online

  27. (As above)

  28. Bismuth Subsalicylate | NIH: StatPearls

  29. The History of Pepto-Bismol | Pepto Bismol

  30. Bismuth Subsalicylate | NIH: StatPearls

  31. Pepto’s in the Pink for a Reason (1992) | Los Angeles Times

  32. Bismuth Subsalicylate | NIH: StatPearls

  33. Is it Safe to Give Pepto Bismol to Kids? | Pepto Bismol

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Here at HealthMatch, we’ve done our best to ensure that the information provided in this article is helpful, up to date, and, most importantly, accurate.

However, we can’t replace the one-to-one advice of a qualified medical practitioner or outline all of the possible risks associated with this particular drug and your circumstances.

It is therefore important for you to note that the information contained in this article does not constitute professional medical or healthcare advice, diagnosis or recommendation of treatment and is not intended to, nor should be used to, replace professional medical advice. This article may not always be up to date and is not exhaustive of all of the risks and considerations relevant to this particular drug. In no circumstances should this article be relied upon without independent consideration and confirmation by a qualified medical practitioner.

Your doctor will be able to explain all possible uses, dosages, precautions, interactions with other drugs, and other potential adverse effects, and you should always talk to them about any kind of medication you are taking, thinking about taking or wanting to stop taking.

Curious about clinical trials?

Access the latest treatments and medications. unavailable elsewhere - entirely free of charge. We make it easy to take part.