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PetDosageChart

Antidiarrheal / Gastroprotectant · For Dogs

Pepto Bismol dosage reference for dogs (Bismuth Subsalicylate)

This page's standard weight-based reference is 8.75 mg per kg (3.97 mg per lb), with every 8 hours, up to 3 doses in 24 hours recorded as the reference frequency. Use the calculator to see the arithmetic for your dog's weight, then confirm the indication, product, and actual dose with a veterinarian.

Onset
30-60 minutes
Duration
6-8 hours
Class
Antidiarrheal / Gastroprotectant

Weight-based calculator estimate from the references listed on this page. This page has not been independently DVM-reviewed — see our methodology .

This information is for educational purposes only. Always consult your veterinarian before giving medication to your pet. Do not use this calculator for emergencies, overdoses, pregnancy, very young animals, very old animals, pets with liver/kidney disease, or pets taking multiple medications.

Sources and review process

Each medication page lists the references recorded for its data. The calculator math and editorial presentation are maintained by PetDosageChart; a page is independently DVM-reviewed only when a named reviewer byline appears. See our methodology and limitations.

Bismuth Subsalicylate (often known by brand names such as Pepto Bismol) is an antidiarrheal / gastroprotectant commonly used in veterinary medicine for diarrhea, nausea, upset stomach, and gas. Understanding the correct dosage, administration, and potential side effects of Bismuth Subsalicylate is critical for your dog’s safety and well-being.

This page’s reference for dogs is about 8.75 mg of bismuth subsalicylate per kg (about 4 mg per lb) every 8 hours, with a range of 5.8–17.5 mg/kg per dose and no more than 52.5 mg/kg in 24 hours. That is the conservative end of published veterinary dosing: the Merck Veterinary Manual lists 1–3 mL/kg per day of the regular-strength liquid (17.5 mg per mL), split into doses. Do not give it for more than 2 days without talking to your veterinarian, and never give it to cats.

All amounts on this page are milligrams of bismuth subsalicylate, not millilitres. Regular-strength Pepto Bismol liquid contains 262 mg per 15 mL (17.5 mg per mL), so the 8.75 mg/kg standard reference is about 0.5 mL per kg, roughly 1 teaspoon (5 mL) per 22 lb. A regular-strength chewable tablet contains 262 mg, which matches the standard reference for a dog of about 66 lb (30 kg). Ultra/Max-strength liquid is twice as concentrated (525 mg per 15 mL), and Children’s Pepto is a different drug (calcium carbonate).

Calculator Warning: Use this only as an educational estimate. Your veterinarian may prescribe a different dose based on your pet’s condition, age, weight, other medications, and medical history.

What the source establishes

Lists bismuth subsalicylate for dogs and cats at 1–3 mL/kg by mouth per 24 hours in divided doses. With regular-strength liquid at 17.5 mg/mL, that is 17.5–52.5 mg/kg per day; split into three doses it is about 5.8–17.5 mg/kg per dose.

The table gives a volume of a standard suspension, not a product-specific mg dose, and it is not advice to treat an individual dog. It lists cats as well, but the same manual warns that salicylate toxicosis is especially likely in cats.

Merck Veterinary Manual: Antidiarrheal Drugs (table) — Bismuth subsalicylate row.

States there is no precise dose for animals, that practically all of the salicylate is absorbed in dogs and cats, that salicylate toxicosis is possible especially in cats, and that the black feces it causes can interfere with checking for intestinal bleeding.

A pharmacology overview, not a dosing protocol for an individual dog.

Merck Veterinary Manual: Drugs Used to Treat Diarrhea in Monogastric Animals — Mucosal Protectants and Adsorbents; bismuth subsalicylate.

Regular-strength liquid contains 525 mg bismuth subsalicylate per 30 mL (17.5 mg/mL; 262 mg per 15 mL), with 261 mg salicylate per 30 mL. This is the concentration used to convert this page's mg results to mL.

This is the human OTC label; its dosing directions are for people and do not apply to dogs. Ultra/Max-strength products are more concentrated. Regular-strength chewable tablets are listed on DailyMed at 262 mg each.

Pepto-Bismol suspension Drug Facts label (Procter & Gamble, DailyMed) — Active ingredient; Other information.

Describes cats as more sensitive to salicylate toxicity and says they should never be given this medication, and lists vomiting, diarrhea, melena, abdominal pain, pale gums, altered mental status, difficulty breathing, and dehydration as signs of toxicity.

Poison-control guidance for exposures; it does not set a therapeutic dose.

American College of Veterinary Pharmacists Pet Poison Control: Bismuth Subsalicylate — Toxicity signs; cats.

Bismuth Subsalicylate Dosage Calculator for Dogs

Enter your dog’s weight below to estimate the Bismuth Subsalicylate dose in mg from the 8.75 mg/kg reference. To convert a result to regular-strength liquid, divide the mg by 17.5 to get mL. Your veterinarian may adjust it for your dog’s age, condition, and other medications, so treat the result as an educational starting point, not a prescription.

Dosage Calculator · 01

Enter your dog's weight

Quick Dosage Chart

Typical Bismuth Subsalicylate amounts for common dog weights, for quick reference:

Dosage Chart · 02

Pepto Bismol weight-based reference chart for dogs

Scroll sideways to see full table

Pepto Bismol weight-based reference chart. Educational arithmetic, not a prescription.
Weight Lower Reference Standard Reference Upper Reference Frequency
5 lbs (2.3 kg) 13.2 mg 19.8 mg 39.7 mg every 8 hours, up to 3 doses in 24 hours
10 lbs (4.5 kg) 26.3 mg 39.7 mg 79.4 mg every 8 hours, up to 3 doses in 24 hours
15 lbs (6.8 kg) 39.5 mg 59.5 mg 119.0 mg every 8 hours, up to 3 doses in 24 hours
20 lbs (9.1 kg) 52.6 mg 79.4 mg 158.7 mg every 8 hours, up to 3 doses in 24 hours
25 lbs (11.3 kg) 65.8 mg (0.25 × 262mg) 99.2 mg 198.4 mg (0.75 × 262mg) every 8 hours, up to 3 doses in 24 hours
30 lbs (13.6 kg) 78.9 mg 119.0 mg 238.1 mg every 8 hours, up to 3 doses in 24 hours
40 lbs (18.1 kg) 105.2 mg 158.7 mg 317.5 mg every 8 hours, up to 3 doses in 24 hours
50 lbs (22.7 kg) 131.5 mg (0.5 × 262mg) 198.4 mg (0.75 × 262mg) 396.8 mg (1.5 × 262mg) every 8 hours, up to 3 doses in 24 hours
60 lbs (27.2 kg) 157.8 mg 238.1 mg 476.2 mg (1.75 × 262mg) every 8 hours, up to 3 doses in 24 hours
70 lbs (31.7 kg) 184.1 mg (0.75 × 262mg) 277.8 mg (262mg tablet) 555.6 mg (2 × 262mg) every 8 hours, up to 3 doses in 24 hours
80 lbs (36.3 kg) 210.4 mg (0.75 × 262mg) 317.5 mg (1.25 × 262mg) 634.9 mg every 8 hours, up to 3 doses in 24 hours
90 lbs (40.8 kg) 236.7 mg 357.1 mg (1.25 × 262mg) 714.3 mg (2.5 × 262mg) every 8 hours, up to 3 doses in 24 hours
100 lbs (45.4 kg) 263.0 mg (262mg tablet) 396.8 mg (1.5 × 262mg) 793.7 mg (3 × 262mg) every 8 hours, up to 3 doses in 24 hours
120 lbs (54.4 kg) 315.6 mg (1.25 × 262mg) 476.2 mg (1.75 × 262mg) 952.4 mg (3.5 × 262mg) every 8 hours, up to 3 doses in 24 hours
150 lbs (68 kg) 394.6 mg (1.5 × 262mg) 595.2 mg 1190.5 mg (4.5 × 262mg) every 8 hours, up to 3 doses in 24 hours

Parenthetical tablet amounts are arithmetic comparisons only. They do not account for scoring, release type, concentration, product labeling, or whether this medication is appropriate for an individual animal.

By Weight

Pepto Bismol reference by dog weight

Choose a common weight to open its optional reference page. Use the main medication calculator for a different exact weight.

Common-weight pages are convenience views of the same educational reference, not separate medical recommendations.

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Why Many Vets No Longer Reach for Pepto Bismol

Bismuth subsalicylate is not FDA-approved for dogs, and the Merck Veterinary Manual notes there is no precise dose for animals. Practically all of the salicylate (the aspirin-family ingredient) is absorbed in dogs and cats, so it adds to the effects of aspirin, NSAIDs and steroids. It turns stool black, which can hide intestinal bleeding, and the tablets can show up on X-rays. Most mild diarrhea in otherwise bright dogs settles with a short bland diet, so ask your veterinarian before giving it, and do not use it in a dog that is vomiting repeatedly, lethargic, or passing blood.

Another human antidiarrheal is not an automatic substitute. The Imodium (loperamide) reference for dogs explains its own product and breed-related cautions. Likewise, the metronidazole reference for dogs describes a prescription drug whose use depends on a veterinary diagnosis. Neither link is a recommendation to switch medicines or treat unexplained diarrhea at home.

How to Give Bismuth Subsalicylate to Your Dog

Only give it if your veterinarian has agreed it is appropriate. Measure the regular-strength liquid with an oral syringe rather than a kitchen spoon; a 262 mg chewable tablet is too large for most small dogs. Expect dark or black stool while it is given. You cannot tell this darkening apart from digested blood at home, so tell your veterinarian you gave it, and call them if black stool comes with vomiting, weakness, or pale gums. Never give it to cats: they are especially prone to salicylate poisoning.

It may interact with aspirin, other NSAIDs, corticosteroids, tetracycline antibiotics, anticoagulants, and other salicylate-containing products.

Side Effects and Safety

Common side effects include dark/black stools, darkened tongue, constipation, and mild nausea. More serious side effects can occur, such as salicylate toxicity, bloody stool, severe vomiting, and tremors.

Cautions · 12

When Pepto Bismol should be used with caution or avoided

Some dogs should not take Pepto Bismol, or need a different dose and closer monitoring. Tell your veterinarian about your pet's full health history and every other medication or supplement they take before giving Pepto Bismol.

  • cats
  • bleeding disorders
  • puppies under 12 weeks
  • use with other NSAIDs
  • aspirin allergy

Interactions · 13

Pepto Bismol drug interactions

Pepto Bismol can interact with other drugs. This list is not complete — always give your veterinarian a full list of your dog's medications and supplements.

aspirin
other NSAIDs
tetracycline antibiotics
anticoagulants
corticosteroids
other salicylate-containing products

Calculator Limits · 14

When not to use this calculator

This calculator gives a general educational estimate for a healthy adult dog at a known weight. Do not rely on it in these situations — talk to your veterinarian instead:

  • In an emergency, or after accidental ingestion or a suspected overdose
  • For pregnant or nursing pets
  • For very young or very old dogs
  • For pets with liver disease, kidney disease, or another chronic illness
  • For pets taking several medications at once
  • When you are not sure of your dog's current, accurate weight
  • For combination products that contain additional active ingredients

Overdose · 15

Suspected overdose: what to do

If you think your dog had too much Pepto Bismol, or swallowed any medication by accident, act right away. Do not wait for symptoms to appear.

  • Call your veterinarian or the nearest emergency animal hospital.
  • ASPCA Animal Poison Control Center: (888) 426-4435
  • Pet Poison Helpline: (855) 764-7661

A consultation fee may apply to the poison hotlines. Have the medication packaging ready, and note how much your pet may have taken and when. Do not try to make your pet vomit unless a veterinarian tells you to.

When to Call the Vet

If your dog experiences any of the following, contact your veterinarian or an emergency clinic immediately:

Frequently Asked Questions

Frequently Asked · 07

Questions about this medication

Can I give my dog Pepto Bismol?
Sometimes, but ask your veterinarian first. Bismuth subsalicylate is not FDA-approved for dogs and many vets now prefer other options, because the salicylate (the aspirin-family ingredient) is almost completely absorbed, it interacts with NSAIDs, aspirin and steroids, and the black stool it causes can hide intestinal bleeding. Do not give it to dogs on NSAIDs, aspirin or steroids, to dogs with bleeding disorders, or to pregnant dogs, and never give Pepto Bismol to cats.
How much Pepto Bismol can I give my dog?
This page uses a conservative reference of about 8.75 mg of bismuth subsalicylate per kg (about 4 mg per pound) every 8 hours, with an upper reference of 17.5 mg/kg per dose and no more than 52.5 mg/kg in 24 hours. That follows the Merck Veterinary Manual total of 1-3 mL/kg per day of the regular-strength liquid, split into doses. In regular-strength liquid (17.5 mg per mL) the standard reference is about 0.5 mL per kg, roughly 1 teaspoon (5 mL) per 22 lb, and the upper reference is about 1 mL per kg. The often-quoted "1 teaspoon per 10 lb" is about 19 mg/kg, slightly above this page's upper reference. One 262 mg chewable tablet matches the standard reference for a dog of about 66 lb (30 kg). Do not use it for more than 2 days without veterinary guidance.
Why is my dog's poop black after Pepto Bismol?
Black stool is an expected effect of bismuth subsalicylate: bismuth reacts with sulfur in the gut to form black bismuth sulfide. It goes away after the medication is stopped. The catch is that it looks like digested blood (melena), so it can hide real intestinal bleeding. Tell your vet you gave Pepto Bismol, and call them if your dog also seems weak, has pale gums, vomits, or the black stool continues after stopping.
Can Pepto Bismol hurt a dog?
Yes. Excessive or repeated doses can cause salicylate toxicity, with vomiting, diarrhea, dark tarry stool, abdominal pain, pale gums, rapid breathing, weakness or tremors; small dogs are at most risk of measuring errors. Bismuth tablets can also show up on X-rays and be mistaken for a foreign body. If your dog may have had too much, call your vet, the ASPCA Animal Poison Control Center (888-426-4435) or Pet Poison Helpline (855-764-7661).

Use This Guide Safely · 08

What weight alone cannot tell you

The calculator performs one narrow job: it multiplies your dog's weight by the lower, standard, and upper mg/kg values recorded for Pepto Bismol. It cannot decide whether this drug, indication, formulation, or schedule is appropriate for an individual animal.

Context in this medication record

Commonly listed uses
diarrhea, nausea, upset stomach, gas
Recorded forms
regular-strength liquid (262 mg per 15 mL), regular-strength chewable tablet (262 mg)
Reference timing
every 8 hours, up to 3 doses in 24 hours; onset 30-60 minutes; duration 6-8 hours

Individual checks a calculator cannot perform

  • Confirm the diagnosis and the reason this medication is being considered.
  • Match the exact product, concentration, route, and whether a tablet may be split.
  • Account for age, pregnancy, organ function, genetics, allergies, and prior reactions.
  • Review every prescription, over-the-counter product, and supplement your pet takes.

Recorded cautions

cats; bleeding disorders; puppies under 12 weeks; use with other NSAIDs; aspirin allergy.

Recorded interactions

aspirin; other NSAIDs; tetracycline antibiotics; anticoagulants; corticosteroids; other salicylate-containing products.

These lists reproduce the structured record used by this page and may not be exhaustive. Show your veterinarian the product label and your dog's complete medication list before acting on a number.

Sources · 09

Sources & references

The structured medication record behind this page names the references below. The links open the publisher or official resource; they do not turn this page into a prescription for an individual animal.

Specific citations above support the identified claims. Other source names remain record-level references; further claim review is still needed. Read our methodology and limitations.

Transparency · 11

How this page was made

This page's structured medication record includes Plumb's Veterinary Drug Handbook among its source names. PetDosageChart applies the record's mg/kg values to the entered weight and presents the arithmetic result. A source record is not the same as an individualized prescription or an independent clinical review.

Sources cited
  • Plumb's Veterinary Drug Handbook
  • Merck Veterinary Manual
Calculator formula
Doses scale linearly from a standard basis of 8.75 mg per kg (3.97 mg per lb) of body weight, given every 8 hours, up to 3 doses in 24 hours. The calculator multiplies that basis by your dog's weight and shows an arithmetic comparison with recorded tablet sizes. That comparison does not determine whether a tablet is scored, splittable, or appropriate for your pet.
Editorial owner
Prepared and maintained by the PetDosageChart editorial team, a software-led publisher and not a veterinary practice.
DVM review status
Not independently DVM-reviewed. A named reviewer and review date appear here only after a confirmed review.

More on our methodology and editorial process — how we source, calculate, and review dogs dosage data.

Safety · 10

More resources