Adults and children 12 and older can take 2 Pepto Bismol chewable tablets per dose, up to 8 doses (16 tablets total) in 24 hours. Each chewable tablet contains 262 mg of the active ingredient, bismuth subsalicylate, and you should chew or dissolve them fully before swallowing.
Dosing Schedule for Adults
The standard dose is 2 chewable tablets taken as needed when symptoms appear. You can repeat that dose every 30 minutes to an hour if symptoms continue, but the hard ceiling is 8 doses in a 24-hour period. That works out to 16 individual tablets maximum per day. This dosing applies whether you’re taking Pepto Bismol for diarrhea, nausea, heartburn, or general indigestion.
Don’t take Pepto Bismol for more than 2 days in a row. Using it longer increases the risk of side effects. If your symptoms haven’t improved within those 2 days, that’s a sign something else may be going on and it’s worth talking to a doctor.
Why It’s Not Safe for Kids Under 12
Children under 12 should not take Pepto Bismol chewables. The active ingredient is chemically related to aspirin, and aspirin-like compounds in children carry a risk of Reye’s syndrome, a rare but serious condition affecting the brain and liver. The risk is highest in kids who have or are recovering from a fever-causing illness like the flu or chickenpox. This applies to all forms of Pepto Bismol, not just the chews.
Common Side Effects
The most noticeable side effect is harmless but startling: your tongue and stool can turn black. This happens because bismuth reacts with tiny amounts of sulfur naturally present in your saliva and digestive tract, forming a dark-colored compound called bismuth sulfide. It clears up on its own once you stop taking the product. If you see black stool while taking Pepto Bismol, that’s almost certainly the cause, not a sign of internal bleeding.
Medications That Don’t Mix Well
Because Pepto Bismol contains salicylates (the same family of compounds found in aspirin), it can interact with several types of medication. The most important ones to watch for are blood thinners (anticoagulants), oral diabetes medications, and other painkillers like ibuprofen or aspirin. Taking Pepto Bismol alongside these without guidance from a pharmacist or doctor can increase the risk of side effects from either medication. If you’re on any of these, check before reaching for the chews.