Ordering Recommendation

Use to optimize drug therapy and monitor patient adherence.

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Timing of specimen collection: Pre-dose (trough) draw - At steady state concentration.


Plain red. Also acceptable: Lavender (K2 or K3EDTA) or pink (K2EDTA).

Specimen Preparation

Separate serum or plasma from cells within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.5 mL)

Storage/Transport Temperature


Unacceptable Conditions

Whole blood. Gel separator tubes, light blue (citrate), or yellow (SPS or ACD solution).


After separation from cells: Ambient: 24 hours; Refrigerated: 2 weeks; Frozen: 4 months


Liquid Chromatography-Tandem Mass Spectrometry




1-8 days

Reference Interval

Test Number
Reference Interval
Therapeutic Range: 800-1600 ng/mL
Toxic: Not well established

Interpretive Data

Trazodone is a selective serotonin reuptake inhibitor antidepressant drug indicated for the treatment of major depressive disorder. The pharmacokinetics of trazodone is influenced by drug-drug interactions that induce or inhibit CYP3A4 metabolism. Adverse effects may include sedation, fatigue, headache, blurred vision, nausea, and cardiac arrhythmia. The risk of serotonin syndrome is increased with concomitant use of other serotonergic drugs. Concomitant use of trazodone with anticoagulants and nonsteroidal anti-inflammatory drugs may increase the risk of bleeding.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the U.S. Food and Drug Administration. This test was performed in a CLIA-certified laboratory and is intended for clinical purposes.

Compliance Category

Laboratory Developed Test (LDT)


Hotline History


CPT Codes

80338 (Alt code: G0480)


Component Test Code* Component Chart Name LOINC
3005862 Trazodone_Serum/Plasma 4064-2
* 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.


  • Desyrel
  • desyrel blood level
  • Molipaxin
  • trazodone blood level
Trazodone, Serum/Plasma