Limited effect of magnesium sulphate on torsades de pointes ventricular tachycardia.
A patient with thioridazine-induced torsades de pointes ventricular tachycardia treated with magnesium sulphate is presented. Due to incessant recurrence of tachycardias it was possible to observe the time course of the effect of 1 g intravenous doses. Suppression of torsades de pointes lasted at best for no more than 18 min and a maintenance infusion was not effective without overdrive pacing. Magnesium sulphate may have value as first aid therapy for drug-induced torsades de pointes ventricular tachycardia. However, its effect disappears rapidly, and, therefore, should not alone be relied on as prophylactic treatment.
D004562:Electrocardiography; D005260:Female; D006352:Heart Ventricles / Q000187:drug effects; D006801:Humans; D008278:Magnesium Sulfate / Q000627:therapeutic use*; D008875:Middle Aged; D013406:Suicide, Attempted / Q000517:prevention & control; D013610:Tachycardia / Q000139:chemically induced / Q000188:drug therapy*; D013881:Thioridazine / Q000009:adverse effects / Q000627:therapeutic use
D008278:Magnesium Sulfate; D013881:Thioridazine