NZ Formulary

Magnesium supplements

mag-nee-zee-um

What does it do?

Magnesium supplements increase the amount of magnesium in your body.

Before you start

  • Tell your doctor if you have bowel problems.
  • Tell your doctor if you are pregnant, planning to become pregnant, or breastfeeding.

How should you take it?

Take magnesium supplements regularly as directed with a glass of water. You can take it with or without food.

What if you forget a dose?

If it is nearly time for your next dose, skip the missed dose and take your next dose at the usual time. Otherwise, take the missed dose as soon as you remember. Do not take two doses at the same time.

Can you take other medicines?

Some medicines available without a prescription may react with magnesium supplements including:

  • antacids (e.g. Mylanta®) or products containing aluminium (e.g. Alu-Tab®), calcium (e.g. Calci-Tab®), iron (e.g. Ferro-tab®), or zinc (e.g. Zincaps®) – do not take these within two hours of magnesium supplements
  • products that also contain magnesium (e.g. Centrum®)

Tell your pharmacist or doctor about all medicines or treatments that you may be taking, including vitamins, herbal products or recreational drugs.

What side effects might you notice?

Side EffectsRecommended action

Diarrhoea

Tell your health professional if troublesome

If you notice any other effects, discuss them with your doctor or pharmacist.