Magnesium hydroxide - oral

Patient Medicine Information
Why do I need this medicine?
Magnesium hydroxide is used on its own or together with other medicines to neutralise stomach acid. It helps relieve stomach discomfort, indigestion, or heartburn (food or acid from your stomach backs up into your mouth, leaving a sour or bitter taste).

This medicine may also be used to treat constipation.
How do I take this medicine?
Take Magnesium hydroxide exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.

This medicine is available as a chewable tablet or as an oral suspension.

If you are taking an oral suspension, shake the bottle well before you take it to ensure that the liquid is evenly mixed. Use the measuring spoon or cup provided to measure out your prescribed dose.

The dose of this medicine will be decided by your doctor depending on your condition.

You may stop taking this medicine when you have no more stomach problems or constipation.
What should I do if I have forgotten to take this medicine?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.

DO NOT double a dose under any circumstances.
What should I take note of while taking this medicine?
Inform your doctor if you have the following conditions:
  • kidney disease
  • muscle weakness disorder
  • magnesium-restricted diet
  • stomach pain, nausea or vomiting
  • change in your bowel habits for more than 2 weeks
Let your doctor know if you are pregnant or breastfeeding.

This medicine may affect the level of magnesium, protein, calcium and potassium in your body. If you are going for certain laboratory tests, inform your doctor that you are taking Magnesium hydroxide.
What side effects could I experience?
Magnesium hydroxide may cause diarrhoea. Ensure adequate hydration to replace the fluids lost.

If you experience rectal bleeding, no bowel movement after using this medicine, severe nausea, vomiting, or diarrhoea, alert your doctor immediately.

Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Inform your doctor and pharmacist if you are taking any of these medicines:
  • medicines used to reduce excessive potassium e.g. sodium polystyrene sulfonate, calcium polystyrene sulfonate
  • certain antibiotics e.g. tetracyline
  • medicines to treat fungal infection e.g. ketoconazole, itraconazole
  • medicines for pain and inflammation e.g. ibuprofen, naproxen
  • medicines for osteoporosis (brittle bones) e.g. alendronate, ibandronate
This list does not include all medicines that may interact with Magnesium hydroxide.

Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
What special dietary instructions should I follow?
Avoid alcohol.
How should I store this medicine?
Store in a cool, dry place away from the reach of children. Do not freeze.

Medicines must not be used past the expiry date.
This information is independently developed by MIMS based on magnesium hydroxide - oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2021 MIMS. All rights reserved. Powered by
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