Bioavailability and LH-suppressing effect of different testosterone preparations in normal and hypogonadal men

The therapeutic effectiveness of intramuscularly administered testosterone esters and free testosterone in suppositories was investigated by the measurement of plasma testosterone and LH levels after administration to normal and hypogonadal men. Testosterone levels were elevated above the lower physiological limit for 1 day after 25 mg testosterone one propionate, for 2 days after 50 mg testosterone propionate and for 14 days after 250 mg testosterone oenanthate. LH levels were suppressed for the corresponding periods. Elevated plasma testosterone and suppressed LH levels were maintained by testosterone suppositories (3 x 20 mg for 5 days).