Magnesium Sulfate (MgSO4)

Question 1

Class

Answer 1

Antiarrhythmic
CNS depressant
Anitconvulsant
Electrolyte

Question 2

Actions

Answer 2

For treatment or prophylaxis of seizures due to toxemia of pregnancy by reducing neuronal excitability (anticonvulsant).
Blocks both the transmission of acetylcholine and the amount released, at the motor end plates.
Decreases the incidence of post infarction arrhythmias by increasing membrane stability and decreasing ventricular excitability.
May result in the relaxation of bronchial and vascular smooth muscle which is probably secondary to calcium blockade

Question 3

Indications

Answer 3

Refractory Vfib or Vtach.
Arrhythmias due to dig toxicity.
Hyperreflexemia of toxemia of pregnancy (preeclampsia).
Torades de pointes.
Eclampsia.
Refractory seizures related to hypomagnesemia (especially in alcoholics).
Controversial: refractory bronchospasm not relieved by betas, steriods, or aminophylline.

Question 4

Contraindications

Answer 4

Heart block. Controversial in acute MI pt.

Question 5

Side effects

Answer 5

From too rapid IV administration: flushing, hypotension, sweating, mild bradycardia.
Hypermagnesemia: depressed reflexes, circulatory collapse, flaccid paralysis, respiratory depression or paralysis, diarrhea.

Question 6

Precautions

Answer 6

Monitor ekg and rr, because respiratory collapse is a serious S.E.
Use with caution in renal failure pts.
Ca Cl should be available as an antagonist.
Concurrant use with CNS depressant requires lower dosage.