Magnesium Sulphate inj

Eclampsia, Cerebral palsy, Hypomagnesemia, Torsades de pointes, Barium poisoning

Adult: IV Hypomagnesaemia Symptomatic deficiency: 1-2 g over 5-60 mins, then maintain at 0.5-1 g/hr if needed. Severe: 1-2 g/hr for 3-6 hr, then 0.5-1 g/hr as needed to correct deficiency. Torsades de pointes W/ pulses: Loading dose: 1-2 g over 5-60 mins, then maintain at 0.5-1 g/hr as needed. Pulseless: 1-2 g over 5-20 mins. Barium poisoning 1-2 g. Cerebral oedema 2.5 g. Eclampsia Loading dose: 4-5 g over 10-15 mins, followed by either a continuous infusion of 1 g/hr or deep IM doses of 4-5 g into alternate buttocks 4 hrly. If seizure recurs, an additional IV dose of 2-4 g may be given. Not to exceed 30-40 g/24 hr. IM Hypomagnesaemia Mild deficiency: 1 g 6 hrly for 4 doses. Severe deficiency: Up to 250 mg/kg w/in 4 hr.

Parenteral: Heart block, severe renal impairment, myocardial damage.

Renal impairment, myasthaenia gravis, digitalised patients; pregnancy. Monitor serum-magnesium concentrations.

B

Enhances neuromuscular blockers, digitalis glycosides.

Hypermagnesaemia characterised by nausea, vomiting, flushing, thirst, hypotension, drowsiness, confusion, slurred speech, double vision, bradycardia, muscle weakness. Hypocalcaemia; paralytic ileus.

Magnesium sulfate decreases levels of acetylcholine in motor nerve terminals. It also acts on the myocardium by decreasing the rate of SA node impulse formation and prolonging the conduction time.