PROLONGED HALF-LIFE OF VERAPAMIL IN A CASE OF OVERDOSE - IMPLICATIONSFOR THERAPY

After an overdose of verapamil (2.4 g) in a 59-year-old man the appare nt half-life of verapamil was prolonged (15 h). The most likely mechan ism is rate-limiting absorption, although changes in clearance and vol ume of distribution may contribute. As the elimination half-life of ve rapamil is increased in overdose, therapy may have to be continued for longer than expected. Moreover since the half-life of absorption of v erapamil in overdose may be prolonged, activated charcoal should be gi ven in repeated doses, even if an ordinary-release formulation has bee n taken.