Introduction

Name

• Doxepin.

Class of drug

• Tricyclic antidepressant.

Description

Chemical name

• 3-Dibenz[b,e]oxepin-11(6H)-ylidene-N,N-dimethyl-1-propanamine.

Molecular formula

• C19H21NO.

Physical properties

• Soluble in alcohol.

Storage requirements

• Light resistant container.

Uses

Indications

• Management of pruritus and psychogenic dermatoses where there is a component of anxiety.
  Doxepin is less cardiotoxic than other tricyclics.

Administration

Precautions

Interactions

with other drugs

Anesthetics and anti-arrhythmics

• Increased risk of arrhythmias.

Anti-epileptics

• Tricyclics antagonize the effects of anti-epileptics.

Sedatives

• Enhanced sedative effect.
• Cimetidine → decreased metabolism → increased concentration doxepin.

Adverse Reactions

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• Gido C, Langguth P & Mutschler E (1994) Predictions of in vivo plasma concentrations from in vitro release kinetics: application to doxepin parenteral (i.m.) suspension in lipophilic vehicles in dogs. Pharm Res 11 (6), 800-808) PubMed.
• Brown T C & Leversha A (1979) Comparison of the cardiovascular toxicity of three tricyclic antidepressant drugs: imipramine, amitryptyline, and doxepin. Clin Toxicol 14 (3), 253-256 PubMed.

Other sources of information

• BSAVA Small Animal Formulary. Ramsey I (2017) 9th edn. Cheltenham: BSAVA. 
• Plumb Veterinary Drug handbook. 3rd edn. pp 261-262.