Magnesium Oxide
PronunciationPronunciation: mag-NEE-zee-uhm OX-ide
Class: Antacid
Trade Names
Mag-Ox 400
- Tablets 400 mg
Maox 420
- Tablets 420 mg
Uro-Mag
- Capsules 140 mg
Pharmacology
Neutralizes gastric acid, thereby increases pH of stomach and duodenal bulb; also increases lower esophageal sphincter tone.
Pharmacokinetics
Elimination
Magnesium Oxide is eliminated renally and fecally.
Duration
Duration is 4 to 6 h.
Indications and Usage
Symptomatic relief of upset stomach associated with hyperacidity, including heartburn, gastroesophageal reflux, acid indigestion and sour stomach; relief of hyperacidity associated with peptic ulcer, gastritis, peptic esophagitis, gastric hyperacidity and hiatal hernia. Also used for treatment of hypomagnesemia, or magnesium depletion resulting from malnutrition, restricted diet, alcoholism or magnesium-depleting drugs.
Contraindications
Standard considerations.
Dosage and Administration
AdultsPO 140 mg (caps) 3 to 4 times/day or 400 to 840 mg/day (tabs).
Storage/Stability
Store at room temperature.
Drug Interactions
IronDecreased pharmacological effect of iron.
NitrofurantoinDecreased pharmacological effect of nitrofurantoin.
PenicillamineDecreased pharmacological effect of penicillamine.
TetracyclinesDecreased pharmacological effect of tetracyclines.
Laboratory Test Interactions
None well documented.
Adverse Reactions
GI
Laxative effect (diarrhea); rebound hyperacidity.
Metabolic
Hypermagnesemia.
Miscellaneous
Milk-alkali syndrome.
Precautions
Pregnancy
Category B .
Lactation
Undetermined.
Renal Function
Use caution in patients with renal function impairment to avoid hypermagnesemia and toxicity.
Overdosage
Symptoms
Diarrhea, fluid and electrolyte abnormalities, hypermagnesemia.
Patient Information
- Advise patient that drug may be laxative and cause diarrhea.
- If being used for antacid effect, instruct patient to notify health care provider if symptoms are not relieved or if black, tarry stools or “coffee-ground” vomitus occurs. These symptoms can indicate bleeding.
- Explain that drug should not be used routinely for laxative effect. Advise patient to use other forms of bowel regulation such as increasing fluid intake, mobility and bulk in diet.
- Warn patient not to take other medications within 2 h of antacids.
Copyright © 2009 Wolters Kluwer Health.
More Magnesium Oxide resources
- magnesium oxide Concise Consumer Information (Cerner Multum)
- magnesium oxide MedFacts Consumer Leaflet (Wolters Kluwer)
