Dosing and uses of magnesium-hydroxide-mineral-oil
Adult dosage forms and strengths
magnesium hydroxide/mineral oiL
oral solution
- 1.25mL/5mL
- 300mg/5mL
Laxative
30-60 mL/day (400 mg/5 mL) PO qD HS or divided doses
15-30 mL/day (800 mg/5mL) PO qDHS or divided doses
Antacid
Liquid: 5-15 mL (400 mg/5 mL) PO PRN up to QId
Tablet: (311 mg): 2-4 tablets q4hr PRN up to QId
Other Indications & Uses
Constipation
Pediatric dosage forms and strengths
magnesium hydroxide/mineral oiL
oral solution
- 1.25mL/5mL
- 300mg/5mL
Laxative
<6 years old: Not recommended
6-11 years old
- 15-30 mL/day PO qHS or divided doses
- 7.5-15 mL/day qHS or divided doses
≥12 years old
- 30-60 mL/day (400 mg/5 mL) PO qD HS or divided doses
- 15-30 mL/day (800 mg/5mL) PO qDHS or divided doses
Antacid
Liquid
- <12 years old: Not recommended
- ≥12 years old: 5-15 mL (400 mg/5 mL) PO PRN up to QID
Tablet (311 mg)
- <12 years old: Not recommended
- ≥12 years old: 2-4 tablets q4hr PRN up to QID
magnesium-hydroxide-mineral-oil adverse (side) effects
Frequency not defined
Hypotension
Respiratory depression
Lipid pneumonia if taken when reclined
Excessive bowel activity
Abdominal cramping
Electrolyte imbalance
Muscle weakness
Anal pruritus and irritation
Laxative dependence (Avoid chronic use)
Warnings
Contraindications
Renal failure, existing electrolyte imbalance, appendicitis symptoms, acute surgical abdomen, myocardial damage, heart block, fecal impaction, rectal fissures, intestinal obstruction or perforation, pregnant, bedridden, dysphagia
If currently taking stool softener
Cautions
Renal insufficiency, Mg-restricted diet
If taken at bedtime, pt should not be reclining to avoid aspiration of oil droplets
Do not take within 2 hr of meals; may interfere with food nutrients & vitamins absorption
Pregnancy and lactation
Pregnancy category: C for mineral oil, B for magnesium hydroxide
Lactation: use cautiously in breast feeding as it is unknown whether mineral oil is excreted into breast milk
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of magnesium-hydroxide-mineral-oil
Onset: 30 min-6 hr
Bioavailabilty: 15-30% of magnesium hydroxide, 30-60% for emulsified mineral oiL
Excretion: Mg is mainly excreted by kidney
Mechanism of action
Saline cathartic effect from magnesium hydroxide & emollient laxative effect from mineral oiL
