Testosterone Free / Testosterone Bioavailable / Testosterone Total
2-5 days after setup at PeaceHealth Laboratories’ reference lab.
83519-90 / 84402-90 / 84403-90
Specimen Collection Details
Two 7.5 mL serum separator tubes (SST). Fasting patient preferred. Draw specimen between 6:00 a.m. and 10:00 a.m., if possible, as testosterone levels vary throughout the day.
Allow to clot, centrifuge and separate serum from cells and pour into plastic vial. Refrigerate. Indicate patient age and sex on specimen and test requisition.
7 days refrigerated or 2 months frozen.
4 mL serum.
2 mL serum.
Total testosterone includes free testosterone, weakly bound testosterone (bound to albumin), and tightly bound testosterone (bound to SHBG or sex hormone binding globulin). Because testosterone can dissociate from the albumin carrier and rapidly diffuse into target cells, albumin-bound or weakly bound testosterone is also available to target tissues.