Tacrolimus and Sirolimus, LC/MS/MS

Test Code

CPT Codes
80195, 80197

[36712] Sirolimus, LC/MS/MS
[70007] Tacrolimus, Highly Sensitive, LC/MS/MS

Preferred Specimen
Please see the individual assays for specimen requirements and stabilities.


Collect specimen 1 hour prior to next dose (12 hour trough)

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Clotted blood specimens

Chromatography/Mass Spectrometry

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule
Set up: Mon-Sat; Report available: Next day

Reference Range
No definitive therapeutic or toxic ranges have been established. Optimal blood drug levels are influenced by type of transplant, patient response, time post-transplant, co-administration of other drugs, and drug formulation.
The following trough range is a suggested guideline: 5.0-20.0 mcg/L

Sirolimus Trough: 3.0-18.0 mcg/L

Clinical Significance
Tacrolimus (FK506) and Sirolimus (Rapamycin) are immunosuppressive drugs used in organ transplantation to prevent graft rejection. Therapeutic drug monitoring is useful to optimize dose and avoid toxicity.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.