Enzyme induction by oral testosterone.

The effects of high doses of testosterone on liver function was studied in 6 healthy males. Intravenous antipyrine elimination was used as the primary parameter of liver function. The subjects received 400 mg testosterone orally for 20 days. The half-life of antipyrine decreased from a mean of 8 + or -2.7 to 5.7 + or -2.6 hours by the end of treatment. Excretion of testosterone was significantly (p greater than .0005) higher on Day 21 of the experiment than on Day 1. Treatment had no apparent effect on serum levels of albumin bilirubin prothrombin alanine-amino-transferase and alkaline phosphatases. It is concluded that orally administered testosterone induces its own enzymatic metabolism.