Testosterone, Free and Total, Adult
Label Mnemonic: FTSTM
Epic Lab Code: LAB4140
Downtime Form: A-1a Miscellaneous Request
Chemistry
6240 RCP
356-3527
Specimen(s):
Plasma
Specimen Instructions:
Specimen should ideally be collected between 6:00 - 10:00 a.m.

Not recommended for children 8 years and younger (especially girls) due to lower concentrations of total testosterone that may be below assay limit of detection. For females or children, see the link below for "Testosterone, Free and Total, Females or Children".
Collection Medium:
Plasma Separator Tube 4.5 mL
Minimum:
3 mL whole blood in light green top or TWO Microtainer® devices
Rejection Criteria:
EDTA plasma
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
1 hour (upon receipt in laboratory)
Reference Range:
Testosterone, total Adult Males: 19-49 years old 249-836 ng/dL 50 years and older 193-740 ng/dL Adult Females: 19-49 years old 8-48 ng/dL 50 years and older 2-41 ng/dL Boys <1 month 75-400 ng/dL 1-5 months 14-363 ng/dL 6-24 months Less than 37 ng/dL 2-5 years Less than 19 ng/dL 6-9 years Less than 13 ng/dL 10-11 years 3-327 ng/dL 12-13 years 29-432 ng/dL 14-15 years 40-778 ng/dL 16-18 years 238-1048 ng/dL Tanner stage 1 Less than 15 ng/dL Tanner stage 2 3-432 ng/dL Tanner stage 3 65-778 ng/dL Tanner stage 4 180-763 ng/dL Tanner stage 5 188-882 ng/dL Girls Up to 30 days 20-64 ng/dL 1-5 months Less than 20 ng/dL 6-24 months Less than 9 ng/dL 2-3 years Less than 20 ng/dL 4-5 years Less than 30 ng/dL 6-7 years Less than 13 ng/dL 8-9 years 1-8 ng/dL 10-11 years 3-32 ng/dL 12-13 years 3-50 ng/dL 14-15 years 6-52 ng/dL 16-18 years 9-58 ng/dL Tanner stage I Less than 17 ng/dL Tanner stage II Less than 40 ng/dL Tanner stage III 5-63 ng/dL Tanner stage IV-V 6-58 ng/dL Sex hormone binding globulin Males 10-80 nmol/L Females, non-pregnant 20-130 nmol/L Reference ranges not well established during pregnancy. Free testosterone Males 0-9 years Less than 1 pg/mL 10-11 years Less than 4 pg/mL 12-13 years Less than 68 pg/mL 14-15 years 2-95 pg/mL 16-17 years 26-119 pg/mL 18 years and older 32-168 pg/mL Tanner stage I Less than 3 pg/mL Tanner stage II Less than 15 pg/mL Tanner stage III Less than 68 pg/mL Tanner stage IV 24-117 pg/mL Tanner stage V 28-165 pg/mL Females 0-9 years Less than 1 pg/mL 10-11 years Less than 3 pg/mL 12-13 years Less than 5 pg/mL 14-15 years Less than 6 pg/mL 16-17 years Less than 7 pg/mL 18-30 years 1-5 pg/mL 31-40 years 1-6 pg/mL 41-50 years 1-4 pg/mL 51 years and older Less than 3 pg/mL Tanner stage I 1-12 pg/mL Tanner stage II 4-28 pg/mL Tanner stage III 7-44 pg/mL Tanner stage IV-V 8-43 pg/mL % free testosterone 1.1-2.5%
Interpretive Data:
The concentration of free testosterone is derived from a mathematical expression based on the constant for the binding of testosterone to sex hormone binding globulin.
Methodology:
Electrochemiluminescence Immunoassay
CPT Code:
84403 Testosterone, 84270 Sex Hormone Binding Globulin