Dosing & Uses
Dosage Forms & Strengths
liquid
- 290mg/5mL
tablet
- 100mg (elemental)
Nutritional Supplementation
19-30 years: Men, 400 mg/day; women, 310 mg/day; pregnant women (≤50 years), 350 mg/day; breastfeeding women (≤50 years), 310 mg/day
>30 years: Men, 420 mg/day; women, 320 mg/day; pregnant women (≤50 years), 360 mg/day; breastfeeding women (≤50 years), 320 mg/day
Constipation/Laxative
195-300 mL PO in single daily dose or in divided doses with full glass of water
Alternative: 2-4 tablets PO at bedtime
Acid Indigestion
1 tablet twice daily or as directed by healthcare provider
Dosing Considerations
Should be refrigerated to maintain potency and palatability
Dosage Forms & Strengths
liquid
- 290mg/5mL
tablet
- 100mg (elemental)
Constipation/Laxative
<2 years: Safety and efficacy not established
2-6 years: 60-90 mL PO once or divided doses; not to exceed 90 mL/24hr
6-12 years: 90-210 mL in single dose or in divided doses with full glass of water
>12 years: 195-300 mL PO in single daily dose or in divided doses with full glass of water; alternatively, may administer 2-4 tablets PO at bedtime
Dosing Considerations
Should be refrigerated to maintain potency and palatability
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (0)
Serious - Use Alternative (9)
- baloxavir marboxil
magnesium citrate will decrease the level or effect of baloxavir marboxil by cation binding in GI tract. Avoid or Use Alternate Drug. Baloxavir may bind to polyvalent cations resulting in decreased absorption. Studies in monkeys showed concurrent use with calcium, aluminum, or iron caused significantly decreased plasma levels. Human studies not conducted.
- demeclocycline
magnesium citrate decreases levels of demeclocycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
- dolutegravir
magnesium citrate will decrease the level or effect of dolutegravir by cation binding in GI tract. Avoid or Use Alternate Drug. Administer dolutegravir 2 hr before or 6 hr after taking medications containing polyvalent cations
- doxycycline
magnesium citrate decreases levels of doxycycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
- eltrombopag
magnesium citrate decreases levels of eltrombopag by inhibition of GI absorption. Applies only to oral form of both agents. Contraindicated. Separate by at least 4 hours.
- minocycline
magnesium citrate decreases levels of minocycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
- oxytetracycline
magnesium citrate decreases levels of oxytetracycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
- potassium phosphates, IV
magnesium citrate decreases effects of potassium phosphates, IV by cation binding in GI tract. Avoid or Use Alternate Drug. Magnesium decreases serum phosphate concentration by binding dietary phosphate. Use alternatives if available.
- tetracycline
magnesium citrate decreases levels of tetracycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
Monitor Closely (16)
- bictegravir
magnesium citrate will decrease the level or effect of bictegravir by cation binding in GI tract. Modify Therapy/Monitor Closely. Bictegravir can be taken under fasting conditions 2 hr before antacids containing Al, Mg, or Ca. Routine administration of bictegravir simultaneously with, or 2 hr after, antacids containing Al, Mg, or Ca is not recommended.
- cabotegravir
magnesium citrate will decrease the level or effect of cabotegravir by cation binding in GI tract. Modify Therapy/Monitor Closely. Administer polyvalent cation products at least 2 hr before or 4 hr after taking oral cabotegravir.
- ciprofloxacin
magnesium citrate decreases levels of ciprofloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Coadministration of ciprofloxacin with multivalent cation-containing products may reduce the bioavailability of ciprofloxacin by 90%. Administer ciprofloxacin at least 2 hours before or 6 hours after using these products. Use alternatives if available.
- deferiprone
magnesium citrate decreases levels of deferiprone by enhancing GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Deferiprone may bind polyvalent cations (eg, iron, aluminum, and zinc), separate administration by at least 4 hr between deferiprone and other medications (eg, antacids), or supplements containing these polyvalent cations.
- deflazacort
magnesium citrate and deflazacort both decrease serum potassium. Use Caution/Monitor.
- fleroxacin
magnesium citrate decreases levels of fleroxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- gemifloxacin
magnesium citrate decreases levels of gemifloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- ifosfamide
ifosfamide, magnesium citrate. Either increases toxicity of the other by nephrotoxicity and/or ototoxicity. Modify Therapy/Monitor Closely. Monitor electrolytes and renal function.
- levofloxacin
magnesium citrate decreases levels of levofloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- moxifloxacin
magnesium citrate decreases levels of moxifloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- ofloxacin
magnesium citrate decreases levels of ofloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- omadacycline
magnesium citrate will decrease the level or effect of omadacycline by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Multivalent cation-containing products may impair absorption of tetracyclines, which may decrease its efficacy. Separate dosing of tetracyclines from these products.
- penicillamine
magnesium citrate decreases levels of penicillamine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- sarecycline
magnesium citrate will decrease the level or effect of sarecycline by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Multivalent cation-containing products may impair absorption of tetracyclines, which may decrease its efficacy. Separate dosing of tetracyclines from these products.
- sodium phosphates, IV
magnesium citrate decreases effects of sodium phosphates, IV by cation binding in GI tract. Modify Therapy/Monitor Closely. Magnesium decreases serum phosphate concentration by binding dietary phosphate. Use alternatives if available.
- vitamin D
vitamin D increases levels of magnesium citrate by Other (see comment). Use Caution/Monitor. Comment: Vitamin D can increase serum magnesium concentrations, particularly in the presence of renal impairment. The combined use of vitamin D and magnesium-containing products should be avoided, if possible, in patients with chronic renal failure.
Minor (41)
- amikacin
amikacin decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- amiloride
amiloride increases levels of magnesium citrate by decreasing renal clearance. Minor/Significance Unknown.
- amphotericin B deoxycholate
amphotericin B deoxycholate decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- bazedoxifene/conjugated estrogens
bazedoxifene/conjugated estrogens decreases levels of magnesium citrate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- bendroflumethiazide
bendroflumethiazide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- bumetanide
bumetanide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- calcitonin salmon
calcitonin salmon increases levels of magnesium citrate by decreasing renal clearance. Minor/Significance Unknown.
- chlorothiazide
chlorothiazide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- chlorthalidone
chlorthalidone decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- conjugated estrogens
conjugated estrogens decreases levels of magnesium citrate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- conjugated estrogens, vaginal
conjugated estrogens, vaginal decreases levels of magnesium citrate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- cyclopenthiazide
cyclopenthiazide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- dextrose
dextrose decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- dextrose (Antidote)
dextrose (Antidote) decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- digoxin
digoxin decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- doxercalciferol
doxercalciferol increases levels of magnesium citrate by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
- drospirenone
drospirenone increases levels of magnesium citrate by decreasing renal clearance. Minor/Significance Unknown.
- estradiol
estradiol decreases levels of magnesium citrate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- estrogens conjugated synthetic
estrogens conjugated synthetic decreases levels of magnesium citrate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- estrogens esterified
estrogens esterified decreases levels of magnesium citrate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- estropipate
estropipate decreases levels of magnesium citrate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- ethacrynic acid
ethacrynic acid decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- furosemide
furosemide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- gentamicin
gentamicin decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- glucagon intranasal
glucagon intranasal increases levels of magnesium citrate by decreasing renal clearance. Minor/Significance Unknown.
- hydrochlorothiazide
hydrochlorothiazide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- ibandronate
magnesium citrate decreases levels of ibandronate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
- indapamide
indapamide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- mannitol
mannitol decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- mestranol
mestranol decreases levels of magnesium citrate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- methyclothiazide
methyclothiazide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- metolazone
metolazone decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- neomycin PO
neomycin PO decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- nitrofurantoin
magnesium citrate decreases levels of nitrofurantoin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
- paromomycin
paromomycin decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- sodium polystyrene sulfonate
sodium polystyrene sulfonate increases levels of magnesium citrate by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis.
- spironolactone
spironolactone increases levels of magnesium citrate by decreasing renal clearance. Minor/Significance Unknown.
- streptomycin
streptomycin decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- tobramycin
tobramycin decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- torsemide
torsemide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.
- triamterene
triamterene increases levels of magnesium citrate by decreasing renal clearance. Minor/Significance Unknown.
Adverse Effects
Frequency Not Defined
Abdominal cramping
Diarrhea
Electrolyte imbalance
Hypermagnesemia
Gas formation
Nausea/vomiting
Warnings
Contraindications
Low sodium diet
Cautions
For occasional use only in treatment of constipation; prolonged use for constipation may cause serious adverse effects
To be used under the supervision of a physician when administered to patients with sodium or manesium restricted diet, kidney dysfunction, nausea/vomiting/abdominal pain with sudden change in bowel habits persisting over 2 weeks
Use with caution in patients with myasthenia gravis or other neuromuscular disease
Avoid use in renal failure, existing electrolyte imbalance, appendicitis or acute surgical abdomen, myocardial damage or heart block, fecal impaction or rectal fissures, intestinal obstruction or perforation, dehydration
Discontinue use and consult healthcare provider if bowel movement does not occur or rectal bleeding develops
Pregnancy & Lactation
Pregnancy category: A
Lactation: Use in nursing mothers appears to be safe
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
Mechanism of Action
Increases peristaltic activity of the colon; promotes bowel evacuation by causing osmotic retention of fluid
Absorption
15-30% absorbed
Onset: 0.5-6 hr or less
Elimination
Excretion: Urine (mainly)