Ordering Recommendation

Use to optimize dosing and monitor patient adherence.

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Predose (trough) levels should be drawn.


Lavender (EDTA) or pink (K2EDTA).

Specimen Preparation

Transport 1 mL whole blood. (Min: 0.25 mL)

Storage/Transport Temperature


Unacceptable Conditions

Serum or plasma. Specimens left at room temperature for longer than 24 hours. Clotted specimens.


Ambient: 24 hours; Refrigerated: 1 week; Frozen: 2 months


Quantitative Liquid Chromatography-Tandem Mass Spectrometry




1-2 days

Reference Interval

Effective February 18, 2014

Therapeutic Range:
Kidney transplant (in combination with Cyclosporine): 4-12 ng/mL
Toxic value: Greater than 25 ng/mL

Interpretive Data

A range of 12-20 ng/mL has been suggested for liver transplant. The optimal therapeutic range for a given patient may differ from this suggested range based on the indication for therapy, treatment phase (initiation or maintenance), use in combination with other drugs, time of specimen collection relative to prior dose, type of transplanted organ, and/or the therapeutic approach of the transplant center.

Compliance Category

Laboratory Developed Test (LDT)


Sirolimus (Rapamune) whole blood concentrations can be measured by either chromatographic or immunoassay methodologies. These two methodologies are not directly interchangeable and the measured sirolimus whole blood concentration depends on the methodology used. Reference ranges may vary according to the specific immunoassay or HPLC-MS/MS test. Generally, immunoassays have been reported to have a positive bias relative to HPLC-MS/MS assays due to the detection of antibody cross-reactivity with sirolimus metabolites.

Hotline History


CPT Codes



Component Test Code* Component Chart Name LOINC
0098467 Sirolimus by HPLC-MS/MS 29247-4
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • Rapamune
  • Rapamycin
Sirolimus by Tandem Mass Spectrometry