Antacid medicines - Who cannot take antacid medicines?

Antacids aren't suitable for everyone and sometimes they need to be taken with caution or avoided completely.

Use in children

Many antacid medicines aren't recommended for children under the age of 12.

Antacids containing calcium aren't recommended for long-term use in children because they can interfere with the rate that calcium is absorbed into the body and carried through the bloodstream. The right levels of calcium are vital for healthy bones and childhood development.

Prolonged use of antacids containing calcium can also lead to muscle weakness and cramps.

There have also been a number of cases linking the prolonged use of antacids containing magnesium and aluminium with rickets, a developmental disorder in infants that causes the bones to soften and weaken.

Always read the patient information leaflet (PIL) that comes with a medicine to ensure it's suitable for children. Check the correct dosage and seek advice from your GP or pharmacist about giving antacids to children under 12 years of age.

Use in pregnancy

Most types of antacids are considered to be safe to take during pregnancy. However, seek advice from your GP or pharmacist before taking antacids if you're pregnant or breastfeeding.

Use with other conditions

Sometimes, the use of some antacids isn't recommended if you have certain health conditions.

Speak to your GP or pharmacist if you have an existing health condition and are unsure whether antacids are suitable for you. You can also check the PIL that comes with all medication to ensure they're suitable for you.

Online copies of PILs can be found on the Medicines and Healthcare products Regulatory Agency (MHRA) and electronic Medicines Compendium (eMC) websites.

Use with other medicines

Taking antacids can sometimes interfere with your body’s ability to absorb other medications you may be taking. Therefore, you may be advised to stop taking other medication while you're taking antacids.

For example, you may not be able to take calcium supplements for a condition such as osteoporosis at the same time as some antacids. Antacids can also alter the effectiveness of some antibiotics.

However, it's important never to stop taking a medication prescribed for you without first consulting your GP or another suitably qualified healthcare professional.