Magnesium Hydroxide Dosage

Medically reviewed by Drugs.com. Last updated on Aug 11, 2023.

Usual Adult Dose for Constipation

CONCENTRATED ORAL SUSPENSION (2400 mg/10 mL): 3600 to 7200 mg (as magnesium hydroxide) orally per day, given once a day in divided doses, or as directed

• Maximum dose: 7200 mg/day
• Duration of therapy: Up to 7 days

ORAL SUSPENSION (1200 mg/15 mL): 2400 mg to 4800 mg (as magnesium hydroxide) orally per day, given once a day, in divided doses, or as directed

• Maximum dose: 4800 mg/day
• Duration of therapy: Up to 7 days

ORAL LIQUID (400 mg/5 mL): 2400 to 4800 mg (as magnesium hydroxide) orally once a day

• Maximum dose: 4800 mg/day
• Duration of therapy: Up to 7 days

Comments:

• In most patients, effects are usually seen within 30 minutes to 6 hours of administration
• Single doses should be taken at bedtime.
• Each dose should be taken with 8 ounces of water.

Use: Relief of occasional constipation/irregularity

Usual Adult Dose for Dyspepsia

CONCENTRATED ORAL SUSPENSION (2400 mg/10 mL): 1200 mg (as magnesium hydroxide) orally up to 4 times a day as needed

• Maximum dose: 4800 mg/day
• Duration of therapy: 7 days

ORAL LIQUID (400 mg/5 mL): 400 to 1200 mg (as magnesium hydroxide) orally up to 4 times a day

• Maximum dose: 4800 mg/day
• Duration of therapy: Up to 7 days

Comments:

• Concentrated suspension doses may be taken with water.
• Dosage cups should not be used to measure oral liquid doses.

Uses:

• Treatment of acid indigestion
• Treatment of heartburn
• Treatment of upset/sour stomach

Usual Pediatric Dose for Constipation

CONCENTRATED ORAL SUSPENSION (2400 mg/10 mL):
Under 12 years: Data not available

12 years and older: 3600 to 7200 mg (as magnesium hydroxide) orally per day, given once a day or in divided doses

• Maximum dose: 7200 mg/day
• Duration of therapy: 7 days

ORAL SUSPENSION (1200 mg/15 mL):
Under 6 years: Data not available

6 to 11 years: 1200 mg to 2400 mg (as magnesium hydroxide) orally per day, given once a day, in divided doses, or as directed

• Maximum dose: 2400 mg/day
• Duration of therapy: Up to 7 days

12 years and older: 2400 mg to 4800 mg (as magnesium hydroxide) orally per day, given once a day, in divided doses, or as directed

• Maximum dose: 4800 mg/day
• Duration of therapy: Up to 7 days

ORAL LIQUID (400 mg/5 mL):
Under 2 years: Data not available

2 to 5 years: 400 mg to 1200 mg (as magnesium hydroxide) orally once a day

• Maximum dose: 1200 mg/day
• Duration of therapy: Up to 7 days

6 to 11 years: 1200 mg to 2400 mg (as magnesium hydroxide) orally once a day

• Maximum dose: 2400 mg/day
• Duration of therapy: Up to 7 days

12 years and older: 2400 mg to 4800 mg (as magnesium hydroxide) orally once a day

• Maximum dose: 4800 mg/day
• Duration of therapy: Up to 7 days

TABLETS:
Under 2 years: Data not available

2 to under 6 years:

• Initial dose: 400 mg to 1200 mg (as magnesium hydroxide) orally once a day or in divided doses
• Maximum dose: 1200 mg/day
• Duration of therapy: Up to 7 days

6 to under 12 years:

• Initial dose: 1200 mg to 2400 mg (as magnesium hydroxide) orally once a day or in divided doses
• Maximum dose: 2400 mg/day
• Duration of therapy: Up to 7 days

Comments:

• In most patients, effects are usually seen within 30 minutes to 6 hours of administration.
• Some experts recommend: Caregivers of children who fail to have a bowel movement within 6 hours of administration should contact the child's healthcare provider.
• Single doses should be taken at bedtime.
• Each dose should be taken with 8 ounces of water.

Use: Relief of occasional constipation/irregularity

Usual Pediatric Dose for Dyspepsia

CONCENTRATED ORAL SUSPENSION (2400 mg/10 mL):
Under 12 years: Data not available

12 years and older: 1200 mg (as magnesium hydroxide) orally up to 4 times a day or as needed

• Maximum dose: 4800 mg/day
• Duration of therapy: 7 days

ORAL LIQUID (400 mg/5 mL):
Under 12 years: Data not available

12 years and older: 400 to 1200 mg (as magnesium hydroxide) orally up to 4 times a day

• Maximum dose: 4800 mg/day
• Duration of therapy: Up to 7 days

Comments:

• Concentrated suspension doses may be taken with water.
• Dosage cups should not be used to measure oral liquid doses.

Uses:

• Treatment of acid indigestion
• Treatment of heartburn
• Treatment of upset/sour stomach
• Relieves acid indigestion, heartburn, and sour stomach

Renal Dose Adjustments

Dose adjustment(s) may be required; however, no specific guidelines have been suggested. Caution recommended.

Liver Dose Adjustments

Data not available

Precautions

CONTRAINDICATIONS:

• Patients with an allergic reaction to the active component or any of the ingredients

Safety and efficacy of concentrated oral suspensions have not been established in patients younger than 12 years.

Safety and efficacy of some oral liquids, oral suspensions, and tablets have not been established in patients younger than 6 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• Oral liquid/suspension: Shake well prior to measuring dose; measure with the included measuring device.
• Antacid: May be taken with water.
• Laxative: Take with a full glass of water.

Storage requirements:

• Oral liquid/suspension: Close tightly when not in use; avoid freezing

Patient advice:

• Advise patients to speak to their healthcare provider if they become pregnant, intend to become pregnant, or are breastfeeding.
• Patients should be instructed to avoid using products if the tamper evident feature(s) are torn, broken, and/or missing.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer