Effects of non-steroid antirheumatic agents on microsomal drug-metabolizing enzymes of rat liver.

Abstract The effects of several non-steroid antirheumatic drugs on ascorbic acid excretion in urine, hexobarbital sleeping time, liver fresh weight, ascorbic acid concentration in the liver and amidopyrine N -demethylation by 15,000 g liver supernatant of the rat were investigated. The drugs tested were acetylsalicylic acid, amidopyrine, benzydamine, nufenamic acid, indomethacin, mefenamic acid, sodium salicylate and salicylamide. There are differences in effects between various agents. Of the eight drugs tested, only amidopyrine increased microsomal liver enzyme activities as phenobarbital. Neither phenobarbital-like induction nor inhibition of phenobarbital induction are common properties of non-steroid antirheumatic drugs.