pharmacokinetics of testosterone pharmacokinetics of testosterone the pharmacology of testosterone, an androgen and anabolic steroid (aas) medication and naturally occurring steroid hormone, concerns its pharmacodynamics, pharmacokinetics, and various routes of administration. testosteroneclinical dataroutes ofadministrationoral, buccal, sublingual, intranasal, transdermal (gel, cream, patch, solution), vaginal (cream, gel, suppository), rectal (suppository), intramuscular or subcutaneous injection (oil solution, aqueous suspension), subcutaneous implant (pellet)drug classandrogen, anabolic steroidpharmacokinetic databioavailabilityoral: very low (due to extensive first pass metabolism)protein binding97.0–99.5% (to shbg and albumin)metabolismliver (mainly reduction and conjugation)elimination half-life2–4 hoursexcretionurine (90%), feces (6%) testosterone is a naturally occurring and bioidentical aas, or an agonist of the androgen receptor, the biological target of androgens like endogenous testosterone and dihydrotestosterone (dht). testosterone is used by both men and women and can be taken by a variety of different routes of administration. routes of administration