Doxepin cream relieves eczema-associated pruritus within 15 minutes and is not accompanied by a risk of rebound upon discontinuation

Abstract

Doxepin hydrochloride 5% cream has been previously demonstrated to be effective for relief of pruritus associated with atopic dermatitis and lichen simplex chronicus. In these studies, no evaluations prior to 12 h after the first application, or following discontinuation of topical doxepin therapy, were performed. The current study was done to investigate the onset of action of topical 5% doxepin cream and to ascertain whether discontinuance of doxepin therapy is associated with ‘rebound’ worsening of pruritus. A total of 120 patients with atopic dermatitis or lichen simplex chronicus with moderate to severe pruritus were treated with 5% doxepin cream in a single-blind treatment period (days 0 to 7) followed by a double-blind treatment period (days 7 to 14) in which patients were randomized to receive either doxepin or vehicle cream to evaluate the effects of cessation of active therapy. Pruritus evaluations performed 15 min following application of doxepin cream demonstrated significant antipruritic activity compared with baseline as measured by visual analogue scales of pruritus severity (P< 0.001) and pruritus relief (P< 0.001). Of the 120 patients, 75% reported reductions in pruritus severity in just 15 min and 84% reported such reductions by 120 min following doxepin cream application. Decreasing pruritus severity and increasing pruritus relief continued significantly through day 7. A statistically significant (P<0.001) improvement in both the pruritus severity rating and the physician's global evaluation of pruritus relief was present on day 7 and continued to day 14 compared with baseline in both treatment groups. Eczema severity was significantly improved on both days 7 and 14 in all treatment groups compared with baseline (P<0.001), with significant continued improvement in the doxepin group on day 14 compared with day 7 (P=0.011). Adverse experiences were predominantly mild to moderate in severity and decreased throughout the study. Within 15 min of application, topically applied 5% doxepin cream provided significant antipruritic activity in patients with atopic dermatitis and lichen simplex chronicus. After completing a 7-day treatment period, it was possible to replace active treatment with an emollient without a rebound effect being observed.

Key Words:

• Doxepin
• Therapy
• Clinical investigation
• Eczema
• Atopic dermatitis