Testosterone, Free, Bioavailable and Total, MS

Send Outs
  • Test Code: LAB1232237
  • Interface Code: 1232237
Department: Send Outs
Last Updated: 10/8/2026
Important Note:

7/30/2026: Current Turn-around Time has been extended by 4 days due to instrument issues.

Synonyms

QUEST: 14966  | Bioavailable Testosterone, Testosterone Free & Weakly Bound, test, total test, free test | LAB8390, LAB173 | 

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: 4.0 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)