Absolute bioavailability of testosterone after oral administration of testosterone-undecanoate and testosterone

Eur J Drug Metab Pharmacokinet. 1986 Apr-Jun;11(2):145-9. doi: 10.1007/BF03189840.


The plasma levels of testosterone (T) were measured after oral administration of 25 mg T and 40 mg testosterone-undecanoate (TU) in a group of young women by a specific radioimmunoassay. Plasma levels were compared to those after intravenous administration of 1.5 micrograms testosterone/kg to another group of young women for determination of absolute bioavailability. Due to the high metabolic clearance rate of 24.5 ml/min/kg absolute systemic availability of free testosterone was calculated to 3.56 +/- 2.45%. Oral administration of testosterone undecanoate leads only to an absolute testosterone bioavailability of 6.83 +/- 3.32%.

Publication types

  • Comparative Study

MeSH terms

  • Administration, Oral
  • Adult
  • Biological Availability
  • Female
  • Half-Life
  • Humans
  • Metabolic Clearance Rate
  • Testosterone / administration & dosage
  • Testosterone / analogs & derivatives*
  • Testosterone / blood*


  • Testosterone
  • testosterone undecanoate