An adrenergic neuron-blocking drug similar in effects to GUANETHIDINE. It is also noteworthy in being a substrate for a polymorphic cytochrome P-450 enzyme. Persons with certain isoforms of this enzyme are unable to properly metabolize this and many other clinically important drugs. They are commonly referred to as having a debrisoquin 4-hydroxylase polymorphism.
3,4-dihydro-2(H)-isoquinolinecarboxamidine (sulfate); oxidative metabolism of this drug is used to assay and model drug metabolism in general, especially genetic, ethnic, and individual pharmacokinetic differences.