Magnesium Sulphate inj
Indications
Magnesium Sulphate inj is used for:
Eclampsia, Cerebral palsy, Hypomagnesemia, Torsades de pointes, Barium poisoning
Adult Dose
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.
Child Dose
Renal Dose
Administration
Contra Indications
Parenteral: Heart block, severe renal impairment, myocardial damage.
Precautions
Renal impairment, myasthaenia gravis, digitalised patients; pregnancy. Monitor serum-magnesium concentrations.
Pregnancy-Lactation
Interactions
Enhances neuromuscular blockers, digitalis glycosides.
Adverse Effects
Side effects of Magnesium Sulphate inj :
Hypermagnesaemia characterised by nausea, vomiting, flushing, thirst, hypotension, drowsiness, confusion, slurred speech, double vision, bradycardia, muscle weakness. Hypocalcaemia; paralytic ileus.
Mechanism of Action
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.