Oral testosterone, a reappraisal.

A microparticulate form of free testosterone was given orally to 6 hypogonadal men. Plasma levels were followed after a 200-mg dose, and a double-peak effect was observed. This suggests that particles of different sizes were absorbed at different rates. The clinical and biochemical effects were observed over a 2-month period, on a dose of 200 mg twice daily, taken in place of the usual androgen replacement. The results indicate that absorption is not sufficiently reliable for routine use. The large doses required to achieve therapeutic levels, make oral administration of free testosterone impractical.