doxepin SINEQUAN

Class: TCA/​3° Amine Dibenzoxepine Derivative
FDA Indications: Psychotic Depressive Disorders With Associated Anxiety Including Involutional Depression & Manic-depressive Disorders, Psychoneurotic Patients With Depression And/or Anxiety, Depression/Anxiety Assoc W/ Alcoholism, Depression/Anxiety Assoc W/ Organic Disease, Sleep Maintenance Insomnia (Silenor®)
Off-Label Use: Anxiety, Insomnia, Treatment Resistant Depression, Neuropathic Pain, Chronic Idiopathic Urticaria
Forms: 10, 25, 50, 75, 100, 100, 150mg capsule; 3, 6mg Silenor® tab; 5% topical; 10mg/mL po soln
Dose Range: 75-300 mg/day
Starting: 25 mg qd qhs, ↑ by 25 mg q3-7 days, max dose 300 mg qd
Stopping: ↓ 50% x3 days, then ↓ another 50% x3 days, then D/C entirely.
Monitoring: Suggested plasma level 500-950 nmol/L

NAMI drug fact sheet

Contraindications: Concomitant use of MAOIs; patient s/p MI; coadministration of other QT-prolonging agents; h/o QT ↑ or arrhythmia; caution in patients with hypo-K+ or hypo-Mg2+
Serious Side Effects: 5HT syndrome; ↓ seizure threshold; QT↑, arrhythmias, tachycardia, orthostatic hypotension
Conditional Risk of TdP
Side Effects: anticholinergic side effects, weight gain, sexual dysfunction
1° MOA: Tricyclic antidepressant
Target: SERT, NET, H1, H2, α1, M1, 5HT2A
t½: 15 (8-24)° TMAX: 2-4°
Substrate of: 2D6, 2C19; 1A2, 2C9
Inhibits: ∅ ; Induces:
Active Metabolites: Desmethyldoxepin (t½ 28-52°)
  • - DO NOT CO-PRESCRIBE WITH MAOIs (need a 14-day washout period)
  • - caution combining with other CNS depressants & anticholingerics
  • - VPA may ↑ levels
  • - low doses may be useful in treating insomnia in the last third of the night, i.e. "late insomnia"
  • - the most anti-histaminergic of all the TCAs
Special Populations

Category C—A case-control study showed ∅ ↑ congenital malformations with 1st trimester use & a review (n=209) showed ∅ assoc with congenital malformations or developmental delay.

RID 1.2-3%; contraindicated d/t significant hypotonia & sedation

Avoid due to its anticholinergicity and high sedation, especially when combining with other CNS depressants and/or anticholingerics. Caution regarding orthostatic hypotension (fall risk!). Can impair cognition.

2019 BEE℞S Recommendation: At low doses (≤6 mg/day), safety profile comparable to that of placebo. At doses > 6mg, avoid d/t being highly anticholinergic, sedating, and propensity to cause orthostatic hypotension.

No dosage adjustment necessary.

All TCAs are hepatically metabolzed, highly protein bound and will accumulate, and associated with ↑ LFTs.


Developed & Designed by Kevin M. Nasky, D.O. • Built with Bootstrap, PHP & MySQL • Hosted by SiteGround
Last updated February 29 2024 20:54:18. Disclaimer: This website does not provide medical advice, nor is it a substitute for clinical judgment.