Amitriptyline

Test Code

423

CPT Codes
80335

Includes

Amitriptyline, Nortriptyline and Total

Preferred Specimen

3 mL serum collected in a red-top tube (no gel)

Patient Preparation
Collect at steady-state trough concentration. Specimen should be collected >12 hours after dose.

Minimum Volume

1.5 mL

Other Acceptable Specimens

Plasma collected in an EDTA (lavender-top) tube, sodium heparin or lithium heparin (green-top) tube

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 5 days
Refrigerated: 7 days
Frozen: 30 days

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

Gross hemolysis • Gel barrier/serum separator tube

Methodology
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 FDA. 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

Total

100-250 mcg/L

Clinical Significance

The tricyclics are used to treat depression. Nortriptyline is an active metabolite of Amitriptyline. Therapeutic drug levels are monitored to assist the physician assessing therapeutic response and to 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.