1. About Pepto-Bismol
It works by protecting your stomach and the lower part of your food pipe from stomach acid. It is also a mild antacid, which helps reduce excess stomach acid and eases any discomfort.
Pepto-Bismol comes as tablets and a liquid that you drink. You can only buy it from pharmacies.
2. Key facts
- Pepto-Bismol can be taken by adults over the age of 16 years.
- You can take it with or without food.
- Speak to a doctor if your symptoms are not any better after 2 days.
- If you're allergic to aspirin (or any of the ingredients in Pepto-Bismol) check with a pharmacist before taking this medicine.
- This medicine is also sold under the brand name Pepti-Calm.
3. Who can and can't take Pepto-Bismol
Pepto-Bismol can be taken by most adults and young people from the age of 16 years.
Do not take this medicine if you are pregnant or breastfeeding.
Pepto-Bismol is not suitable for some people. To make sure this medicine is safe for you, tell your doctor or pharmacist if you have:
- had an allergic reaction to Pepto-Bismol, aspirin or any other medicines in the past
- an allergy to amaranth or aspartame
- a problem with blood clotting
- a rare inherited illness called phenylketonuria - the chewable tablets contain aspartame
Pepto-Bismol liquid and tablets both contain a colouring called amaranth. Some people can have an allergic reaction to amaranth.
4. How and when to take it
Only take Pepto-Bismol when you need it. You can take it for occasional heartburn, indigestion or an upset stomach.
Do not take Pepto-Bismol for more than 2 days.
If your symptoms have not improved within 2 days, speak to your doctor.
How much to take
Liquid: a single dose is 30ml. Use the measuring cup that comes with the medicine to make sure you get the right amount.
Tablets: a single dose is 2 tablets. Chew the tablets or let them dissolve on your tongue.
If you need to, repeat this dose every 30 to 60 minutes. Do not take more than 8 doses in 24 hours.
How to take it
You take Pepto-Bismol with or without food.
If you're taking Pepto-Bismol for diarrhoea, make sure you drink plenty of fluids to avoid dehydration.
What if I take too much?
Taking too much Pepto-Bismol can increase the risk of side effects.
Side effects may include feeling or being sick, feeling confused, dizzy or tired, deafness, or ringing or buzzing in your ears.
Urgent advice: Speak to a doctor or pharmacist now if:
- you take too much Pepto-Bismol
5. Side effects
You're unlikely to get any side effects from Pepto-Bismol if you follow the instructions for taking it.
One common side effect is your poo or your tongue turning black. This is harmless.
This happens when bismuth (the active ingredient in this medicine) comes into contact with small amounts of sulphur in your saliva and digestive system. They combine to form bismuth sulfide, a black substance. This side effect usually goes away when you stop taking the medicine.
If your tongue or your poo is still black after 3 days, or after you've stopped taking Pepto-Bismol, speak to your doctor or a pharmacist.
Tell your doctor or a pharmacist if you have any other side effects that bother you or do not go away.
Serious allergic reaction
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to Pepto-Bismol.
Immediate action required: Call 999 or go to A&E if:
- you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
- you're wheezing
- you get tightness in the chest or throat
- you have trouble breathing or talking
- your mouth, face, lips, tongue or throat start swelling
You could be having a serious allergic reaction and may need immediate treatment in hospital.
These are not all the side effects of Pepto-Bismol. For a full list see the leaflet inside your medicines packet.
You can report any suspected side effect to the UK safety scheme.
6. Pregnancy and breastfeeding
Do not take Pepto-Bismol if you're pregnant or breastfeeding.
It's best to try to treat your indigestion without taking a medicine. It can help to:
- eat smaller meals and more often
- avoid fatty or spicy foods, and avoid alcohol and cigarettes
- raise one end of your bed a little, so your head is higher than your stomach
- avoid lying down immediately after eating
- drink water between meals rather than with meals
If this advice does not work, speak to your doctor or a pharmacist. They will be able to recommend the most suitable medicine for you and your baby.
Non-urgent advice: Tell your doctor if you're:
- trying to get pregnant
7. Cautions with other medicines
Pepto-Bismol contains salicylates (also found in aspirin) and can interfere with certain other medicines.
To make sure Pepto-Bismol is safe for you, tell your doctor or a pharmacist if you are taking:
- blood thinners (anticoagulants)
- tablets or other oral medicines for diabetes
- medicine for gout
- doxycyline or minocycline, or any other tetracycline antibiotics
If you're taking tetracycline antibiotics, you need to leave a 2-hour gap before taking Pepto-Bismol.
It's safe to take paracetamol at the same time as Pepto-Bismol. Do not take other painkillers, like ibuprofen or aspirin, with Pepto-Bismol without talking to your doctor or pharmacist first. This could make your symptoms worse.
Mixing Pepto-Bismol with herbal remedies and supplements
There's very little information about taking herbal remedies and supplements with Pepto-Bismol.
For safety, tell your doctor or pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements.
8. Common questions
How does Pepto-Bismol work?
How long does it take to work?
How long will I take it for?
Are there other indigestion medicines?
Can I take Pepto-Bismol with other indigestion medicines?
Will it affect my fertility?
Will it affect my contraception?
Can I drive or ride a bike?
Can I drink alcohol with it?
Can lifestyle changes help?
Page last reviewed: 13/08/2019
Next review due: 13/08/2022