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Bismuth Subsalicylate Uses, Side Effects, and Precautions

Linda Crampton is an experienced teacher with a first-class honors degree in biology. She writes about the scientific basis of disease.

Bismuth subsalicylate can be a useful treatment for gastrointestinal problems.

Bismuth subsalicylate can be a useful treatment for gastrointestinal problems.

A Potentially Useful Medicine

Bismuth is an unusual and medically helpful element. It’s classified as a heavy metal since it has a high atomic mass. Heavy metals are often toxic to humans, but bismuth is much less toxic than the other members of the group. In fact, when it’s combined with other elements to form a compound (also known as a salt), bismuth is used as a medicine to help treat gastrointestinal problems. These problems include diarrhea, an upset stomach, a peptic ulcer, and heartburn.

A bismuth medicine is most commonly taken in the form of bismuth subsalicylate. A popular brand name of this medicine is Pepto-Bismol. Bismuth subsalicylate is frequently sold over the counter as a thick liquid. The liquid is usually coloured pink, giving it the name "pink bismuth". Tablets of the product are often coloured pink as well.

A ball and stick model of a bismuth subsalicylate molecule (carbon atoms are black, hydrogen grey, oxygen red, and bismuth purple)

A ball and stick model of a bismuth subsalicylate molecule (carbon atoms are black, hydrogen grey, oxygen red, and bismuth purple)

Creation and Historical Use of the Medicine

The pink formulation of bismuth subsalicylate has been used as a medicine for gastrointestinal distress since the early twentieth century. It was created by a doctor to treat a childhood disorder known as cholera infantum or summer diarrhea. This disorder involved the sudden onset of diarrhea and vomiting. The symptoms of the disorder were often severe and were sometimes fatal. The doctor added a pink colour to his concoction in order to make it more appealing to children.

The term "cholera infantum" is no longer used. The condition as described in the old literature no longer exists in many countries. Improved sanitation has probably been a big help. There is some debate about the cause of the original condition, although it's believed to have been an infection. It may have been caused by multiple pathogens.

Bismuth Subsalicylate and Gastrointestinal Problems

Bismuth subsalicylate is the active ingredient in Pepto-Bismol and equivalent store brands of pink bismuth. It's also present in the latest version of Kaopectate. It can be bought in a tablet form as well as in a liquid one. The pink colour of the medications is artificial. The chemical is actually white in colour.

The exact mechanism of action of bismuth subsalicylate isn’t known. It’s thought to relieve discomfort by coating the lining of the digestive tract, soothing inflammation, killing bacteria that cause diarrhea, and decreasing the release of fluid into the digestive tract. The salicylate component may suppress the action of prostaglandins, chemicals that can cause inflammation.

Helicobacter pylori is the cause of most peptic ulcers.

Helicobacter pylori is the cause of most peptic ulcers.

Bismuth Subsalicylate and Peptic Ulcers

Peptic Ulcers and Their Cause

Bismuth compounds are sometimes used to help treat peptic ulcers. A peptic ulcer is a sore on the lining of the stomach or in the first part of the small intestine, which is known as the duodenum. The ulcer is also known as a stomach or gastric ulcer when it's present in the stomach and as a duodenal ulcer when it's present in the duodenum.

Most peptic ulcers are caused by a bacterium called Helicobacter pylori. The bacterium penetrates the protective mucus lining of the stomach, causing inflammation and pain. Other stomach bacteria are killed by the acid in the stomach, but not H. pylori. This pesky creature escapes the acid by entering the mucus. Interestingly, for an unknown reason not everybody with an H. pylori infection develops ulcers.

Some Stomach Ulcer Treatments

Bismuth subsalicylate is thought to form a coating on top of the stomach mucus, protecting the ulcer from an acid attack. Bismuth also kills ulcer bacteria, although an antibiotic is better at doing this and is usually given to the patient instead of or in addition to the bismuth compound.

Other types of ulcer medicines are generally prescribed on their own or in addition to bismuth subsalicylate as well. These include a medication called a proton pump inhibitor and one known as an H2 (histamine) blocker. Both medications reduce the amount of acid secreted by the stomach.

Follow a Doctor's Advice

A person should never self-diagnose an ulcer or try to treat one entirely with bismuth subsalicylate. Salicylates may increase the risk of gastrointestinal bleeding. If someone has been diagnosed with an ulcer, they should take doctor-prescribed medicines for the condition. They should also ask for their doctor's opinion about adding bismuth subsalicylate to the treatment regimen. If you frequently have to take a bismuth medication to relieve recurring pain of an unknown origin, you need to visit a doctor to find the cause of the pain.

Possible Side Effects of Bismuth Compounds

Although bismuth compounds are very useful in medicine, there are some concerns about their use. A high concentration of the compounds taken over a long period of time may damage nerves and the kidneys. In most people, a short treatment of stomach or intestinal problems by a bismuth compound causes no ill effects, however, especially when the dosage recommendations on the product label are followed. Most of the bismuth is eventually removed from the body in the stool and only a small amount is absorbed into the body.

One side effect of treatment by bismuth compounds is that the stool may become dark. The colour change is said to be harmless. It's caused by the presence of bismuth sulfide, which forms when bismuth joins with sulfur in the digestive tract. The tongue may darken too, for the same reason. The dark colour may last for several days after taking the medicine.

If bismuth is given in the form of bismuth subsalicylate, there may be additional side effects. Some people are very sensitive to salicylates in their diet. In these people, bismuth subsalicylate may cause allergy symptoms such as a headache, stomach pain, a rash, or difficulty breathing. Sensitive people may also experience ringing in the ears and temporary hearing loss.

Bismuth subsalicylate may interfere with the absorption of antibiotics belonging to the tetracycline group, so it shouldn't be taken at the same time as these antibiotics. A doctor's advice should be followed regarding a treatment schedule.

Salicylates can cause ringing in the ears (tinnitus) in sensitive people.

Salicylates can cause ringing in the ears (tinnitus) in sensitive people.

Reye's Syndrome and Salicylates

Aspirin, also known as acetylsalicylic acid, and bismuth subsalicylate have chemical similarities, as their names suggest. Children and teenagers shouldn’t take aspirin when they are recovering from viral infections, especially the flu (influenza) and chicken pox. In this situation, aspirin may increase the risk of a child developing Reye’s syndrome (or Reye syndrome), although the link is not well understood. Reye's syndrome is a rare but potentially fatal illness that can damage the brain and liver. Some doctors recommend that children never be given aspirin.

It’s not known for certain whether non-aspirin salicylates pose the same risk with respect to Reye’s syndrome as aspirin. In the United States, the FDA (Food and Drug Administration) allows companies to state that bismuth subsalicylate is safe for children aged twelve and above. Some doctors say that like aspirin, bismuth subsalicylate shouldn't be given to either children or teenagers when they are recovering from the flu or chicken pox. Some say that children shouldn't be given any salicylates at all.

Since there is uncertainty about the dangers of salicylates for children, a parent who is concerned about the situation should seek their doctor's advice. Pregnant women and nursing mothers should definitely check with their doctor before taking bismuth subsalicylate. Fortunately, Reye's syndrome is rare, but it may be devastating if it occurs.

A Interesting Product for Occasional Use

Despite the possible side effects, bismuth subsalicylate can be very useful as a medicine and is a good product for many people to have in their homes. Some thought should be given to its use, however. It can be a big help for an occasional problem but it shouldn't be used frequently or for a long time.

Like most medicines, a bottle of bismuth subsalicylate should have an expiry date written on it. Since most of us use the medicine very occasionally (if we use it all), the product may have expired when we want to use it again. If we want to know whether our problem is quickly helped by the liquid, a fresh container would be useful. People with certain pre-existing medical conditions or susceptibilities to certain health problems should seek their doctor's advice about the advisability of taking bismuth subsalicylate.


  • The National Institutes of Health (NIH) provides information about the uses and safety of bismuth subsalicylate.
  • WebMD also gives information about the substance.
  • The treatment for an H. pylori infection must be prescribed by a doctor. The Mayo Clinic website describes the common treatments for H. pylori infections that are causing peptic ulcers, including the use of bismuth subsalicylate.
  • The Nature Journal website has information about bismuth and the historical use of bismuth subsalicylate.

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

© 2011 Linda Crampton


Linda Crampton (author) from British Columbia, Canada on March 05, 2012:

Hi, Debbie. Thanks for the visit and the comment! I hope that your health problems improve.

Deborah Brooks Langford from Brownsville,TX on March 05, 2012:

Alicia I am book marking this. I have these problems.. thanks for this great information


Linda Crampton (author) from British Columbia, Canada on June 22, 2011:

I am so happy to be your friend too, Prasetio!! I love reading your hubs. Thank you very much for your comment and vote.

prasetio30 from malang-indonesia on June 22, 2011:

I always know I will be greeted with your talent in giving valuable information. I am proud to be your friend. Again, this was knowledgeable hub. I learn much from you. Rated up as usual. Cheers..


Linda Crampton (author) from British Columbia, Canada on June 21, 2011:

Thank you very much for your comment, Chatkath!

Kathy from California on June 20, 2011:

Another learning experience for me Alicia! Thank you for sharing your wealth of knowledge :-)