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Pepto Bismol is a common over-the-counter (OTC) drug that may help control occasional symptoms of simple digestive issues, such as indigestion, heartburn, and diarrhea.
Pepto Bismol is an antacid. It is available in a variety of forms, including capsules and liquids, and comes in a range of strengths. Some people may experience specific side effects, such as very dark or black stool, after taking Pepto Bismol. However, these side effects are generally temporary and harmless.
The drug may also interact with other medications, such as anticoagulants, or blood thinners. A person should only use Pepto Bismol or similar products for a short period to treat occasional symptoms. Anyone dealing with chronic digestive symptoms should speak with their doctor.
This article provides an overview of Pepto Bismol, including its uses, risks, and instructions.
Bismuth subsalicylate is the main active ingredient in Pepto Bismol. It is an antacid medication that also works to lower inflammation in the digestive system.
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These combined efforts may help with digestive symptoms such as:
In some cases, and always under a doctor’s guidance, people may use Pepto Bismol and other drugs to help treat infections caused by the bacteria H. pylori and symptoms that arise from them. Sometimes, a doctor may recommend it to treat symptoms of chronic digestive disorders.
Some people also find the antibacterial effects of Pepto Bismol useful when traveling to unfamiliar areas where the local bacteria may infect their digestive system and cause traveler’s diarrhea.
No one should self-diagnose an underlying issue and use Pepto Bismol to treat it. Anyone whose symptoms get worse or last more than 2 days should contact a doctor for a full diagnosis.
Pepto Bismol comes in various forms, including:
- oral liquid
- oral liquid capsules
- oral tablets
- chewable tablets
Each option contains various strengths and dosages of bismuth subsalicylate designed for specific symptoms and how fast a person needs relief.
A chewable tablet for symptoms in children is also available. However, the active ingredient in this product is calcium carbonate, not bismuth subsalicylate.
Anyone taking Pepto Bismol to treat occasional digestive symptoms should follow the instructions on the label.
The original liquid Pepto Bismol includes a 30 milliliter (ml) cup, which is one dose, delivering 525 milligrams (mg) of bismuth subsalicylate. The Pepto Bismol website recommends taking:
- One 30 ml dose every 30 minutes as needed for stomach upset, nausea, heartburn, and indigestion
- One 30 ml dose every 30 minutes or two doses every hour for diarrhea or traveler’s diarrhea
It also warns not to take more than eight doses in 24 hours.
When using the original chewable tablets, one dose is two tablets. The recommended dose is:
- Two tablets every 30 minutes or four tablets every hour for diarrhea
- Two tablets every 30 minutes for stomach upset, nausea, heartburn, and indigestion
Similarly, do not take more than eight doses (16 tablets) in 24 hours.
Pepto Bismol Extra Strength is a more concentrated liquid but delivers the same amount of active ingredient per recommended dose — 525 mg of bismuth subsalicylate in 15 ml of liquid.
For children under the age of 12, use children’s versions of similar medications or talk to a doctor before using Pepto Bismol.
Do not take more Pepto Bismol than directed, even if symptoms do not clear up.
Anyone using Pepto Bismol or similar drugs to treat more serious issues, such as infection, must follow the specific instructions from their doctor.
Side effects from using bismuth subsalicylate are not common. The most common side effects are a very dark or black stool, and darkening on the tongue. This is a reaction to the bismuth and is temporary. The discoloration should go away when the person stops taking the product.
Most people do not experience any serious side effects. However, people who are allergic to salicylate, which is a chemical found in aspirin, may experience more severe side effects. Anyone who is allergic to these ingredients can talk to their doctor about alternatives to using Pepto Bismol.
In rare cases, a person may experience ringing in their ears or hearing loss. If this occurs, the person should stop taking the product immediately and contact a doctor.
An extreme reaction might result in internal bleeding in the stomach or intestines. Anyone experiencing symptoms such as severe cramps, bloody or dark, sticky stool, or vomit that looks similar to coffee grounds, should stop taking the drug and contact a doctor immediately.
Children or teens who are recovering from chickenpox or the flu should not take Pepto Bismol. Taking Pepto Bismol in these situations could cause Reye’s syndrome. Symptoms of Reye’s syndrome include changes in behavior, nausea, vomiting, and seizures. This is a rare reaction, but it can be a medical emergency.
There is little evidence that Pepto Bismol causes harmful side effects during pregnancy, though there is little research to say that it is safe either.
Similarly, it is unclear if bismuth subsalicylate passes through the breastmilk.
Pregnant or breastfeeding women should always consult a doctor before using Pepto Bismol or any medicine that contains bismuth subsalicylate.
There are several possible interactions when taking Pepto Bismol.
Most notably, Pepto Bismol may interact with blood-thinning medications. Anyone taking anticoagulant medication should contact their doctor or pharmacist before using Pepto Bismol.
The medication may act similarly to aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) and so may compound their effect. Anyone taking aspirin and NSAIDs should talk to their doctor. It is also possible for the drug to interact with other medicines that people take to treat chronic conditions, such as gout or diabetes.
Anyone considering using Pepto Bismol for symptoms should tell their doctor or pharmacist about any medications they are taking before choosing Pepto Bismol.
Anyone who has an active ulcer or bleeding problem should not use bismuth subsalicylate.
Anyone who is allergic to aspirin or other salicylates should talk to their doctor before using Pepto Bismol. Likewise, anyone who reacts to NSAIDs should also contact their doctor first.
People with a history of bleeding disorders should only use Pepto Bismol under the guidance of a doctor.
Anyone who has gout or diabetes should also contact their doctor before using the drug.
People may also have reactions to other inactive ingredients in the medication and should check all ingredients before using the product.
Pepto Bismol is generally safe when a person uses it correctly, but it is still possible to overdose. Signs of an overdose include:
- extreme dizziness
- ringing in ears
- partial deafness
- changes in breathing
- mental fog or confusion
Anyone experiencing these symptoms should contact medical services or Poison Control on 1-800-222-1222. Anyone experiencing severe symptoms should contact emergency services.
Pepto Bismol is a name brand for a popular OTC drug, bismuth subsalicylate.
Pepto Bismol is just one type of antacid. There are many other types for people to choose between, which are available at drug stores and online.
Antacids are generally effective for treating mild forms of digestive upset and symptoms related to indigestion. Some people may experience a harmless reaction to the drug that causes their stool or tongue to become darker or turn black. This should go away as the person stops using the drug.
Pepto Bismol is only for temporary relief from symptoms. Anyone experiencing symptoms that get worse or last more than a couple of days should stop taking Pepto Bismol and see a doctor.