Magnesium sulfate
(Redirected from MgSO4)
See critical care quick reference for drug doses by weight.
General
- Type: Antiarrhythmics
- Dosage Forms: IV
- Common Trade Names: None
Adult Dosing
Cardiac arrest
- Loading dose = 1-2gm in 10mL D5W over 1-2min
Spontaneous circulation
- Loading dose = 1-4gm in 50-100 D5W over 20-60 min
Eclampsia
- Initial: 4 g magnesium sulfate 50% solution (400mg elemental magnesium) to a 10% or 20% solution and give IV over 3 to 4 minutes OR 5mg IM in each buttock
- Maintenance: 1 to 2 g/hr IV until paroxysms cease
Pediatric Dosing
- Torsades: 25 to 50mg/kg rapid infusion over several minutes
Cardiac
- 25-50mg/kg IV x 1
See critical care quick reference for drug doses by weight.
Special Populations
- Pregnancy Rating: D (despite being drug of choice for eclampsia!)
- Lactation: infant risk minimal
- Renal Dosing: for severe renal impairment, max dose 20g/48 hours
- Adult
- Pediatric
- Hepatic Dosing
- Adult
- Pediatric
Indications
- QT prolongation
- Torsades
- Refractory v-tach/fib (regardless of Mg level)
- Eclampsia
- Hypomagnesemia
- Barium poisoning
Contraindications
- Allergy to class/drug
Adverse Reactions
Serious
- Hypotension (rare)
- Heart block
- CNS depression
- Respiratory depression
Common
Pharmacology
- Half-life:
- Onset of action = Immediate
- Duration of action = 30min
- Metabolism:
- Excretion: Renal
Mechanism of Action
- Increases vasomotor tone
- Prolongs AV conduction; prolongs refractoriness