Pharmacokinetic Properties of Testosterone Propionate in Norman Men

Abstract

The pharmacokinetic characteristics of testosterone propionate were studied in normal men after a single im dose of 25 mg testosterone propionate-19,19,19-d3. Plasma levels of testosterone propionate-19,19,19-d3, its active metabolite testosterone-19,19,19-d3, and endogenous testosterone were measured by gas chromatography-mass spectrometry. Testosterone propionate-19,19,19-d3 was gradually transferred from the im injection site to the systemic circulation. The plasma levels of testosterone propionate-19,19,19-d3 were maintained at 2-4 ng/ml between 3 and 36 h after administration. Plasma testosterone-19,19,19-d3 levels were maintained above the physiological testosterone level for 48 h, while plasma levels of endogenous testosterone changed little.

Contribution of Lymphatically Transported Testosterone Undecanoate to the Systemic Exposure of Testosterone after Oral Administration of Two Andriol Formulations in Conscious Lymph Duct-Cannulated Dogs

“…In the lymph duct cannulated dog, the apparent bioavailability calculated from the ratio of the dose normalized systemic serum AUC values after oral and i.v. administration (determined using a stable TU isotope, which is not expected to exhibit an in vivo isotope effect; Baba et al, 1979Baba et al, , 1980Shinohara et al, 1980Shinohara et al, , 1988Fujioka et al, 1986Fujioka et al, , 1989Shinohara and Baba, 1990) is equivalent to the fraction of the dose systemically available after absorption via the portal vein.…”

Tissue Engineering of the Reproductive System

“…Androgen replacement modalities include oral administration of testosterone tablets or capsules (Franchimont et al, 1978;Snyder and Lawrence, 1980;Sokol et al, 1982;Canteril, 1984;Fujioka et al, 1986;Stuenkel et al, 1991;Chang, 1993;Bennett, 1998;Ferrini and Barrett-Connor, 1998;McClellan and Goa, 1998;Wilson et al, 1998). When taken orally, testosterone preparations are largely rendered metabolically inactive during the "first pass" through the liver.…”

Testosterone

“…Studies applying gas chromatography-mass spectrometry that allow discrimination between endogenous testosterone and exogenously administered deuterium-labelled testosterone propionate-19, 19, 19-d3 and its metabolite testosterone-19, 19, 19-d3 were able to show that after intramuscular administration, the androgen ester is slowly absorbed into the general circulation and then rapidly converted to the active unesterified metabolite (Fujioka et al 1986). The ester is then rapidly hydrolysed in plasma, as could be shown by in vitro rat studies (van der Vies 1970) and in vivo human studies (Fujioka et al 1986). Comparisons of the absorption kinetics of different androgen esters clearly show that the half-lifes of the absorption of the esters increase when the esterified fatty acids have a longer chain (van der Vies 1985).…”