CHLORPHENESIN METABOLISM IN RAT AND DOG

The absorption, distribution and metabolic fate of chlorphenesin (3-p-chlorophenoxy-1,2-propanediol) were studied in the rat and dog. After oral ingestion of chlorphenesin-14C, the drug was rapidly absorbed by the rat, and radioactivity reached a peak blood concentration in 30 min. The half-life of serum radioactivity was about 140 min. A distribution study of 3-p-chlorophenoxy-1,2-propanediol-1,3-14C (chlorphensin-1,3-14C) in the rat showed that over half the dose was excreted in the urine after 4 hr, the remainder being principally in the gastrointestinal tract and carcass. A small portion of radioactivity was also recovered as respiratory CO2. Five urinary end-products were identified after administration of the drug. They were (1) 3-p-chlorophenoxylactic acid, (2) p-chlorophenoxyacetic acid, (3) unchanged drug, (4) a conjugate of chlorophenol, and (5) a conjugate of chlorphenesin. © 1969.