Vitamins, minerals, supplements:

Indications for: Magnesium Sulfate Injection

Magnesium deficiency.

Adult Dosage:

Mild deficiency: 1g IM every 6 hours for four doses. Severe deficiency: 250mg/kg IM within a period of 4 hours if necessary; alternatively 5g may be added to one liter of 5% dextrose inj or 0.9% sodium chloride inj for slow IV infusion over a 3-hour period. TPN: usual range: 1–3g (8–24mEq) daily. Severe renal impairment: max 20g in 48 hours.

Children Dosage:

TPN for infants: usual range: 0.25–1.25g (2–10mEq) daily.

Magnesium Sulfate Injection Contraindications:

Heart block. Myocardial damage.

Magnesium Sulfate Injection Warnings/Precautions:

Renal impairment. Monitor serum magnesium levels; if repeated doses are given, test knee jerk reflexes before each dose. Have injectable calcium salt readily available to counteract magnesium intoxication. Elderly. Premature neonates. Pregnancy (Cat.D). Nursing mothers.

Magnesium Sulfate Injection Interactions:

Additive CNS depressant effects with barbiturates, narcotics, other hypnotics; adjust dose. Potentiates neuromuscular blocking agents. Concomitant cardiac glycosides; use extreme caution, heart block may occur.

Adverse Reactions:

Magnesium intoxication (eg, flushing, sweating, hypotension, depressed reflexes, flaccid paralysis, hypothermia, circulatory collapse, cardiac and CNS depression proceeding to respiratory paralysis.


Formerly known under the brand name Sulfamag.

How Supplied:

Contact supplier.