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Why does pepto bismol turn your tongue black?
Answer 1:

Has his happened to you? Someone you know? Kind of creepy, huh?

It turns out that the active ingredient in Pepto-Bismol (bismuth subsalicylate) contains a chemical called bismuth. When a small amount of bismuth combines with trace amounts of sulfur, a black-colored substance (bismuth sulfide) is formed. Your saliva (and also your intestinal tract) can contain trace amounts of sulfur depending on what you have been eating and your individual metabolism, so this is why the black color can form on your tongue (and also in your bowels) - a chemical reaction has occurred! This discoloration is harmless, and it is always temporary. It can last several days after you stop taking Pepto-Bismol depending on your metabolism and how long the pepto bismol remains in your system.

By the way, the FDA-mandated warning for aspirin- and non-aspirin-salicyalte containing products states, "Children and teenagers should not use this medicine for chicken pox or flu symptoms before a doctor is consulted about Reye's syndrome, a rare but serious illness reported to be associated with aspirin." There is no aspirin in Pepto-Bismol, but the active ingredient in Pepto Bismol is a non-aspirin salicylate. Salicylates are commonly used as flavoring agents in food (like wintergreen), and this is what gives Pepto Bismol its "minty" taste.


Answer 2:

The active ingredient in Pepto-Bismol contains bismuth. When a small amount of bismuth combines with trace amounts of sulfur in your saliva and gastrointestinal tract, a black-colored substance (bismuth sulfide) is formed and caused a black stain. This discoloration is temporary and harmless.


Answer 3:

Because I was not familiar with this phenomenon I went straight to the source. The following was taken from the pepto-bismol website:
pepto_bismol

I noticed that Pepto-Bismol sometimes darkens the tongue/stool. Why does this happen and how long does it last?

The active ingredient in Pepto-Bismol contains bismuth. When a small amount of bismuth combines with trace amounts of sulfur in your saliva and gastrointestinal tract, a black-colored substance (bismuth sulfide) is formed. This discoloration is temporary and harmless. It can last several days after you stop taking Pepto-Bismol. Individual bowel habits, your age (the intestinal tract slows down with age), and the amount of the product taken all help to determine how long Pepto-Bismol is in your system.


Answer 4:

Pepto Bismol contains an ingredient called bismuth. Bismuth is one of the ingredients that helps settle your stomach when it is upset. However if you had something to eat that contains sulfate (which includes a wide variety of every day foods), it can react with the bismuth to create a black substance.



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