magnesium sulfate

NATIONAL

CALIFORNIA

VENTURA

policies

category

mechanism

Acts on myocardium by slowing rate of SA node firing and and prolonging conduction time
Triggers cerebral vasodilation reducing ischemia generated by cerebral vasospasm during an eclamptic event

indications

Treatment of polymorphic ventricular tachycardia (torsades de pointes)
Treatment of seizures in eclampsia or preeclampsia with severe features (20 weeks gestation to one week postpartum & no seizure history)

contraindications

Second- or third-degree atrioventricular block without a functioning artificial pacemaker
Myasthenia gravis or other neuromuscular disease
Use with caution in patients with renal impairment

dosing

Adult

Polymorphic ventricular tachycardia (torsades de pointes):

IV, IO: 2 g over 1-2 minutes. If no response or torsades de pointes recurs, may repeat dose immediately

Eclampsia/preeclampsia with severe features, seizure prophylaxis and treatment:

IV, IO: Initial: 4 g over 10 minutes

Pediatric

Polymorphic ventricular tachycardia (torsades de pointes):

IV, IO: 50 mg/kg/dose; maximum dose: 2,000 mg/dose. If no response or torsades de pointes recurs, may repeat dose

administration

bolus over 1-2 minutes

onset

immediate

duration

30 minutes

notes

Adverse effects: Slow or stop infusion if bradycardia, heart block, or respiratory depression occur.
Toxicity: Calcium chloride should be available for treating severe magnesium toxicity (hypotension, respiratory depression) in eclampsia/preeclampsia
Calcium channel blockers: may enhance the adverse/toxic effect of calcium channel blockers (hypotension or muscle weakness)

dosage form

IV solution 1 gram / 2mL (50%), 10 mL and 20 mL vials

adverse reactions

structure