About magnesium oxide
Magnesium supplement and antacid
Used for
- Treats or prevents low magnesium levels.
- Relieves occasional heartburn and acid indigestion.
- Can be used as a laxative for constipation.
Usual adult dose
For low magnesium, dosing varies by need; for heartburn, commonly 400–800 mg as needed. Constipation doses vary by product.
Usual dose in children
For low magnesium, clinician-directed dosing depends on age and need. Not routinely used for children’s heartburn or constipation.
Common side effects
- Diarrhea or loose stools
- Nausea or abdominal cramping
- High blood magnesium, especially with kidney impairment
Important warnings
- Kidney disease increases risk of magnesium buildup.
- Separate from medicines whose absorption magnesium can reduce.
- Seek assessment for persistent constipation or heartburn.
Pregnancy
Generally considered low risk at usual doses; use only as needed and avoid excessive intake.
Breastfeeding
Generally compatible at usual doses; excessive use may cause maternal diarrhea.
Interactions
- Reduces absorption of tetracycline and quinolone antibiotics; separate doses.
- Reduces absorption of bisphosphonates and levothyroxine; separate doses.
- Diuretics and proton-pump inhibitors can alter magnesium levels.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.