Doxepin Synonyms Adapin®; Sinequan®

Test Includes Doxepin, its metabolite N-desmethyldoxepin (nordoxepin), and total activity

Laboratory Core Laboratory

Referral to Reference Laboratory

Request Form Routine Blood Requisition

Phone (212) 305-8600

Availability Daily, 24 hours

Turnaround Time 2-4 days

Specimen Blood

Volume 7 mL

Minimum Volume 2 mL serum

Container Red top tube; do not draw in serum separator tube.

Collection Immediately prior to next dose or at least 12 hours after last dose

Storage Instructions Separate serum and refrigerate.

Reference Range Total doxepin: therapeutic: 100-250

g/L; potentially toxic: >450

g/L

Use Monitor therapeutic drug level; evaluate toxicity

Methodology High performance liquid chromatography (HPLC)