TRICYCLIC ANTIDEPRESSANTS

---

Specimen: 10 mL blood in plain tube.

Method: Immunoassay, chromatography.

Therapeutic Intervals:

Drug:	(nmol/L)	(µg/L)
Amitriptyline	150-900	60-250
Nortriptyline	200-650	50-170
Imipramine	350-1000	100-300
Desipramine	150-550	40-150
Doxepin	300-900	90-250
Trimipramine	300-500	90-150
Dothiepin	150-700	50-200

Application: Therapeutic monitoring; assessment of overdose.

Interpretation: Therapeutic intervals are only approximations; consult pathologist. Owing to the long half-lives of these drugs, some days to weeks are required to reach steady state conditions.

Reference: Gram LF et al. Therap Drug Monit 1982; 4: 17-25. Brathwaite RA et al. Therap Drug Monit 1982; 4: 27-31.

---