Blood test Testosterone (free) + SHBG
Testosterone free (ISSAM) is calculated from the 3 tests performed hereby:
- Testosterone
- SHBG
- Albumin
These three values are also reported separately.
About Testosterone
Testosterone is the main male sex hormone. Most of the testosterone is bound to the transport protein SHBG (Sex Hormone Binding Globulin) and is therefore not biologically active. This test measures the amount of unbound, biologically active testosterone.
The test also measures the amount of Sex Hormone Binding Globulin (SHBG) in blood. SHBG is a protein (globulin) produced by the liver that is able to bind testosterone and estradiol strongly to itself. SHBG then transports these hormones in an inactive form through the body via the blood. Testosterone inhibits SHBG production while estradiol stimulates production.
Click here for the Free Testosterone Calculator