Optimizing doxepin therapy in dermatology: Introducing blood level monitoring and genotype testing.

Optimizing doxepin therapy in dermatology: Introducing blood level monitoring and genotype testing. J Dermatolog Treat. 2020 Apr 29;:1-30 Authors: Myers B, Reddy V, Chan S, Thibodeaux Q, Brownstone N, Koo J Abstract Doxepin, a tricyclic antidepressant, is the most efficacious antipruritic available to dermatologists, however its use is often suboptimal because of significant interindividual variability in doxepin plasma levels and clinical response between patients taking the same dose. As result, the Food and Drug Administration approves a maximum dose of 300 mg of doxepin per day and a 10 mg per cc liquid doxepin concentrate. These allow patients to significantly increase or decrease their dose, due to either a lack of clinical efficacy or side effects at typical dermatologic doses (often 10-25 mg per day). This review initially discusses the unique advantages of doxepin in dermatology. Then, it explores internal and external reasons why doxepin plasma levels and clinical response vary so significantly between patients, including genetic polymorphisms, drug interactions, comorbidities, sex, and ethnicity. Blood level monitoring is introduced, a tool dermatologists can use to optimize doxepin dosing in patients responding subtherapeutically to typical dermatologic doses. Without blood level monitoring, patients initially unresponsive to treatment could be labeled treatment failures when in fact they may be cases of inadequate ...
Source: Journal of Dermatological Treatment - Category: Dermatology Tags: J Dermatolog Treat Source Type: research