Seizure with eclampsia or pre-eclampsia: 4-5 grams IV and undiluted IM injection of up to 10 grams (5 grams into each buttock) simultaneously.
Torsades de Pointes: 1-2 grams IV administered over 5 to 60 minutes.
Hypomagnesemia: 25-50 mg/kg IV or IM every 4 to 6 hours, for 3 to 4 doses, as needed.
DRUG INTERACTIONS: Barbiturates, narcotics or other hypnotics or other drugs that slow brain function may add to the brain depressing effects of magnesium. Magnesium adds to the effect of neuromuscular blocking agents.
PREGNANCY: Magnesium sulfate can cause fetal abnormalities, such as hypocalcemia, skeletal demineralization, osteopenia and other skeletal abnormalities, when administered beyond 5-7 days to pregnant women. It should be used only if clearly needed. If magnesium sulfate needs to be used during pregnancy, the woman should be informed of the potential risks to the newborn.
NURSING MOTHERS: Magnesium sulfate enters breast milk therefore, it is best to be cautious before using it in nursing mothers.
Medically reviewed by Eni Williams, PharmD
FDA Prescribing Information.
Medscape. magnesium sulfate (Rx).
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