Testosterone, Free, Bioavailable and Total, MS

Send Outs
  • Test Code: LAB1232237
  • Interface Code: 1232237
Department: Send Outs
Last Updated: 2/20/2026

Synonyms

LAB8390 | QUEST: 14966  | Bioavailable Testosterone, Testosterone Free & Weakly Bound, test, total test, free test

Ordering Instructions

Administration of STRENSIQ may interfere in certain assays and may falsely elevate values. For patients receiving STRENSIQ, consideration should be given to using alternate methods.

Includes

  • Testosterone, Total, MS
  • Testosterone, Free
  • Testosterone, Bioavailable
  • Sex Hormone Binding Globulin (SHBG)
  • Albumin

 

Specimen Collection

Collection Instructions

Specimen Collection: Blood

 

Container(s): Gold Top (Serum Separator-SST Gel) or Red Top (no gel)

Minimum Volume to Collect: 3.0 mL

 

Collection Instructions:

  • After collection, gently invert tube 8-10 times.
  • Specimen should be processed within 2 hours -- See Processing Instructions.

Processing Instructions

Laboratory, Outpatient or Off-site collection

Processed Specimen: 2.8 mL Serum

Centrifuge/Spin: Yes

Aliquot: Yes

Minimum volume: 1.3 mL 

Processing Instructions:

  • Red-top tube (no gel): Allow blood to clot at room temperature. Centrifuge to separate the serum from the cells and immediately pour serum into a plastic transport tube.
  • Serum separator tube: Allow blood to clot at room temperature, centrifuge, and remove serum from the gel immediately (not to exceed 48 hours) by pouring serum into a plastic transport tube.

 

Transport Instructions

Transport Container: Transport tube

Transport Temperature: Room temperature

 

Rejection Criteria

Gross hemolysis • Grossly lipemic

Specimen Stability and Storage

 

  • Room temperature: 7 days
    Refrigerated: 7 days
    Frozen: 28 days

Performed

Information not provided

Reference Range

See Laboratory Report

Clinical Information

Testosterone, Free, Bioavailable and Total, MS - Helpful in assessing testicular function in males and managing hirsutism, virilization in females.

Performing Laboratory

Quest Diagnostics 

Methodology

Chromatography/Mass Spectrometry • Calculation (CALC) • Spectrophotometry (SP) • Immunochemiluminescent Assay

CPT Code

82040, 84270, 84403

Resources and References

 

Test FAQ

Hypogonadism

Test FAQ

STRENSIQ® (Asfotase Alfa) Assay Interference

Test FAQ

Testosterone Testing

Clinical Focus

Hypogonadism and Low Testosterone in Men: Laboratory Support of Diagnosis and Management

Clinical Focus

Polycystic Ovary Syndrome (PCOS)