Magnesium sulphate oral use: what to know

Magnesium sulphate taken by mouth may draw water into the bowel and cause loose stools or diarrhoea. The intended use, product strength, and your health history determine whether it is appropriate. It should not be confused with other magnesium supplements or with magnesium sulphate given into a vein.

People with kidney disease may be more vulnerable to magnesium building up in the body. Tell a clinician about pregnancy, kidney or heart problems, ongoing diarrhoea, and every medicine or supplement you use. Some products can affect how other medicines are absorbed, so spacing may be advised.

Follow the package or prescription instructions, measure a liquid product with the supplied device, and drink suitable fluids unless a clinician has restricted your intake. Do not take extra doses to make up for a missed dose, and do not continue it for longer than advised without review.

Stop and seek advice if diarrhoea persists, you cannot keep fluids down, or you become unusually weak. Keep the container available so a pharmacist or emergency clinician can identify the exact product.

Get urgent help for severe weakness, confusion, fainting, slow or difficult breathing, an irregular heartbeat, or inability to wake normally after taking magnesium sulphate. Contact a clinician promptly for severe abdominal pain, repeated vomiting, or signs of dehydration.

Ask what the medicine is intended to do, how to measure it, how long to use it, whether it interacts with your other medicines, and which symptoms mean you should stop. Confirm whether a different magnesium product would be safer for your situation.