Lab Dept:

Chemistry

Test Name:

AMITRIPTYLINE AND NORTRIPTYLINE

General Information

Lab Order Codes:

AMNO

Synonyms:

Elavil®; Tricyclic Antidepressants; TCA

CPT Codes:

80152 – Amitriptyline
80182 - Nortriptyline

Test Includes:

Nortriptyline and total Amitriptyline/Nortriptyline reported in ng/mL.

Logistics

Test Indications:

Useful in therapeutic drug monitoring and relief of symptoms of endogenous depression. The test may also be useful to evaluate patient compliance.

Lab Testing Sections:

Chemistry – Sendouts

Referred to:

Mayo Medical Laboratories (Test# AMT/8125)

Phone Numbers:

Minneapolis:

Saint Paul:

612-813-6280

651-220-6550

Test Availability:

Daily, 24 hours

Turnaround Time:

2 – 4 days, test set-up Monday – Saturday

Special Instructions:

Gel tubes are not acceptable.

Specimen

Specimen Type:

Blood

Container:

Red top tube

Draw Volume:

6 - 9 mL (Minimum: 3.3 mL) blood

Processed Volume:

2 - 3 mL (Minimum: 1.1 mL) serum

Collection:

Routine venipuncture

Special Processing:

Lab staff: Centrifuge specimen, remove serum aliquot into a screw-capped round bottom plastic vial. Store and ship at refrigerated temperatures. Forward promptly.

Patient Preparation:

None

Sample Rejection:

Mislabeled or unlabeled specimens

Interpretive

Reference Range:

Amitriptyline and Nortriptyline:

Reference Range: 80 - 200 ng/mL

Nortriptyline:

Reference Range: 70 - 170 ng/mL

Critical Values:

Amitriptyline and Nortriptyline:

Toxic: ≥300 ng/mL

Nortriptyline:

Toxic: ≥300 ng/mL

Note: Therapeutic ranges are for specimens drawn at trough (i.e., immediately before next scheduled dose). Levels may be elevated in non-trough specimens.

Limitations:

N/A

Methodology:

High Performance Liquid Chromatography (HPLC)

References:

Mayo Medical Laboratories (October 2012)

Updates:

3/4/2004: Test moved from MedTox Laboratories to Mayo Medical Laboratories.
10/26/2009: Note change in reference ranges. Plasma specimens no longer accepted.
10/25/2012: Toxic level update from MML.