[Pharmacokinetics of 3H-bamethan in humans]

Pharmacokinetics and metabolism are described for 3H-labelled d,l,-1-(4-hydroxy-phenyl)-1-hydroxy-2-n-butylamino-ethan (bamethane, Vasculat) in man. Following i.v. injection and p.o. ingestion of tablets and aqueous solution identical amounts of 3H-activity are excreted in urine. This fact demonstrates complete enteric absorption. After i.v. injection 40%, after oral ingestion only 30% of dose are excreted unchanged in urine. Therefore, bioavailability is calculated as 75%. A similar result is seen when the areas under the serum level curve are compared. The biological half-life is 2.5 h. Absorption proceeded rapidly peak serum levels are observed at 30 min. There is, however, a considerable first-pass metabolism.