Amitriptyline

1 x 5 mL red top tube, NOT SST

Serum separator (gel) vacutainers must be avoided as the drugs may adhere to the gel.

1.5 mL serum

Minimum Blood Volume for Patients less than 45 kg (100 lb) Including Neonates and Pediatrics

Collect 10-14 hours after last dose for patients on a single daily dose or just before the morning or afternoon dose for those on divided dose schedule.

Includes analysis of it's metabolite Nortriptyline.

For additional information, see Half-life and time to Steady State.

The correlation between dose and plasma concentration is influenced by age, sex, smoking and pharmacogenetics altered by drug-drug interactions (co-administration).

Therapeutic ranges indicate trough levels in serum under steady state conditions.

Amitriptyline + Nortriptyline¹: 288 to 721 nmol/L

Significant cardiovascular toxicity may be associated with levels >1800 nmol/L.

1. Baumann P, Hiemke C, Ulrich S, et al. The AGNP-TDM expert consensus guidelines: Therapeutic Drug Monitoring in Psychiatry. Pharmacopsychiatry 2004; 37:242-265.