INVESTIGATION OF THE POTENTIAL INTERACTION BETWEEN TERFENADINE AND TEDISAMIL IN HUMAN LIVER-MICROSOMES

1. The potential drug-drug interaction of terfenadine and tedisamil ha s been investigated. Terfenadine is a widely used antihistamine drug w ith the potential for QTC prolongation. Tedisamil is a potassium chann el blocking agent known to produce bradycardia and prolong the effecti ve refractory period in man. 2. Tedisamil and terfenadine were incubat ed with human liver microsomes for 30 min at 37 degrees C. No signific ant inhibition of terfenadine biotransformation was seen with 0.1 or 1 0 mu M tedisamil as the formation of the terfenadine alcohol and acid metabolites were unaffected. 3. Based on the In vitro results it is su ggested that tedisamil will not interact pharmacokinetically with terf enadine as it does not impair metabolism of terfenadine.