Medication leaflets

Active substance

Results for the substance calcium carbonate magnesium carbonate

11 results

About this active substance

Calcium carbonate and magnesium carbonate are antacids used to relieve heartburn, acid indigestion and gastro-oesophageal reflux symptoms. They may help when stomach acid causes burning behind the breastbone, a sour taste in the mouth, bloating or discomfort after meals. These medicines reduce symptoms, but they do not treat the underlying cause of reflux.

The two salts work quickly by neutralising excess acid in the stomach. This reduces irritation of the stomach and food pipe and can ease pain within minutes. Their action is mainly local, although some calcium and magnesium may be absorbed. For this reason, high doses or long-term use should be avoided unless a doctor advises it.

They are usually taken as chewable or suckable tablets when needed, following the package leaflet. Do not exceed the recommended daily dose. To avoid reducing the absorption of other medicines, take the antacid 1 to 2 hours apart from antibiotics, levothyroxine, iron, bisphosphonates, digoxin or other important treatments. Avoid large amounts of milk or calcium supplements unless advised.

Side effects are uncommon at normal doses, but may include constipation, diarrhoea, nausea, vomiting or abdominal discomfort. Do not use without medical advice if you have severe kidney disease, kidney stones, high calcium levels or low phosphate levels. See a doctor if symptoms last more than 7 days, or if you have chest pain, weight loss, vomiting blood or difficulty swallowing.