Free testosterone – FTST
Testosterone is an organic chemical compound. It is the main and primary sex hormone found in men. Its production takes place in the testes, but also in small amounts - in both sexes - in the adrenal cortex, and in women also in the placenta and ovaries.

CDT Medicus

Centrum Medyczne Damiana

ClinicLab

Dom Lekarski
Waiting time for the result up to 10 days

NaszLekarz
Waiting time for the result up to 7 days

Przebadani

Synevo
- Test description
- Test results
Free Testosterone (FTST)
Testosterone in the blood is found in its free form (1-4%), bound to with albumin (less than 44%) and bound to the protein SHBG transport protein (about 55%). As bioavailable (BAT), it is considered to be testosterone free and bound to albumin.
The determination of total testosterone concentration reflects the amount of of bound and free hormone, but does not allow assessment of the content of the individual fractions. In many cases, it is sufficient for assessing testosterone synthesis. However, in cases where the concentration of SHBG is abnormal, total testosterone levels do not accurately reflect the amount of bioavailable testosterone. In such situations situations, a better test is to determine the concentration of testosterone free.
Indications for the test
The indications for testing testosterone levels free are as follows:
- assessment of gonadal hormonal function;
- helpful in the diagnosis of adrenal disease, Klinefelter syndrome, polycystic ovary syndrome;
- in women in cases of suspected hirsutism (excessive male-type body hair), menstrual disorders, problems with getting pregnant;
- in men, decrease in libido, erectile dysfunction, fertility;
Reduced free testosterone levels
Reduced levels of free testosterone occur in cases of underdevelopment of the gonads, defects occurring during the synthesis of testosterone, viral infections of the gonads (including testicular inflammation caused by mumps), testicular damage due to mechanical trauma or alcohol abuse, hyperprolactinemia, malnutrition of the patient, and changes in concentrations of transporter proteins.
Increased free testosterone levels
An elevated level of free testosterone can occur as a result of congenital or acquired adrenal hyperplasia, tumors of the testes or adrenal glands, polycystic ovarian syndrome, hyperthyroidism, the presence of ovarian tumors that secrete androgens, the syndrome of Cushing's syndrome, and abnormal concentrations of proteins that bind and transport sex hormones.