[Metabolic interactions of denaverine]

Owing to enzyme induction, the pretreatment of female Wistar rats with denaverine (Spasmalgan) produces a dose-dependent shortening of the hexobarbital sleeping time, corresponding with an increase in aminophenazon-N- and p-nitroanisol-O-demethylation, cytochrome P-450 concentration and NADPH-cytochrome-c-reductase activity in the 9000 g supernatant of liver homogenates and the relative liver weight, but no change in p-nitrophenetol-O-dealkylation and p-nitrophenol-glucuronidation. Our data suggest that denaverine is a phenobarbital-type microsomal enzyme inducer and justify the expectation of drug interactions in case of repeated application of denaverine in the framework of a combined therapy.