Magnesium sulfate Alleviation or elimination of hypocalcemia and hypomagnesemia associated with foscarnet infusion. Excess magnesium appears to decrease the amount of acetylcholine liberated by the motor nerve impulse. Magnesium also acts peripherally producing vasodilation. Magnesium readily crosses the placenta and is distributed into milk.
Magnesium sulfate is excreted by the kidney.
When magnesium sulfate is administered intravenously, the onset of action is immediate and the duration is about 30 minutes. Following intramuscular administration of the drug, the onset of the action occurs in about 1 hour and the duration of action is 3-4 hours. Other Major Uses Magnesium sulfate is mainly used as an anticonvulsant for the prevention and control of seizures in severe preclampsia or in eclampsia. Substance Interactions Concomitant administration with CNS depressants such as barbiturates, opiates, or general anesthetics must be done with careful adjustment of these agents to prevent additive central depressant effects. Concomitant administration of neuromuscular blocking agents should be done with caution.