The metabolism of the anti-inflammatory drug eterylate in rat, dog and man

1. Oral doses of 14C-eterylate were well absorbed by rat and man and excreted mainly in the urine (94% dose by rat in three days and 91% by man in five days). Oral doses to dogs were excreted in similar proportions in both the urine and faeces, although faecal 14C was probably derived in part, from biliary-excreted material.2. Peak plasma 14C and drug concn. were generally reached between one and three hours after oral doses. In humans, only two metabolites, salicylic acid and 4-acetamido-phenoxyacetic acid, were detected in plasma. The latter was cleared more rapidly than the former and hence plasma salicylate concn. reached a peak (10.9 and 19.8 μg/ml in Subjects 1 and 2, respectively) and initially declined with a half-life of about two-three hours. Plasma 4-acetamidophenoxyacetic acid concn. reached a peak (4.3, 10.0 μg/ml, respectively) and declined with a half-life of about one hour.3. Tissue concn. of 14C were generally greater in dogs than in rats. Highest conc. occurred at three hours in dogs and...