<prompt> QT prolongation is caused by:-QuinidineOmeprazoleLidocainePenicillin  <response>: Drugs causing QT prolongation are: Cisapride Astemizole Terfanidine Class 1A anti-arrythmic drugs: Quinidine, Procainamide. Class 3 anti-arrythmic drugs: Bretylium, Ibutilide 