Treatment of Deficiency
- IM IV (Adults ): Severe deficiency: 8–12 g/day in divided doses; Mild deficiency: 1 g every 6 hr for 4 doses or 250 mg/kg over 4 hr.
- IM IV (Children >1 mo): 25–50 mg/kg/dose every 4–6 hr for 3–4 doses (max single dose = 2 g).
- IV (Neonates ): 25–50 mg/kg/dose every 8–12 hr for 2–3 doses.
Seizures Associated with Eclampsia/Pre-Eclampsia
- IV (Adults ): 4–6 g loading dose over 15–30 min at onset of labor or induction/cesarean delivery, followed by 1–2 g/hr continuous infusion for ≥24 hr after delivery (max infusion rate = 3 g/hr). If seizure occurs while receiving magnesium, an additional bolus of 2–4 g may be administered over ≥5 minutes. Max dose = 40 g/24 hr.
- IM (Adults ): 10 g loading dose administered as 5 g in each buttock at onset of labor or induction/cesarean delivery, followed by 5 g every 4 hr for ≥24 hr after delivery.
Torsades de Pointes
- IV (Adults ): 1–2 g over 15 minutes. If no response or torsades de pointes recurs, may repeat dose up to a total of 4 g in 1 hour; may follow with a continuous IV infusion of 0.5–1 g/hr.
- IV (Infants and Children): 25–50 mg/kg/dose (max dose = 2 g).
Bronchodilation
- IV (Adults ): 2 g single dose.
- IV (Children ): 25 mg/kg/dose (max dose = 2 g).
Parenteral Nutrition
- IV (Adults ): 4–24 mEq/day.
- IV (Children ): 0.25–0.5 mEq/kg/day.