The use of nanoencapsulation to decrease human skin irritation caused by capsaicinoids

摘要: Capsaicin, a topical analgesic used in the treatment of chronic pain, has irritant properties that frequently interrupt its use. In this work, effect nanoencapsulation main capsaicinoids (capsaicin and dihydrocapsaicin) on skin irritation was tested humans. Skin tolerance novel vehicle composed chitosan hydrogel containing nonloaded nanocapsules (CH-NC) also evaluated. The nanoencapsulated (CH-NC-CP) did not cause irritation, as measured by an erythema probe visual scale, while formulation free (chitosan gel with hydroalcoholic solution [CH-ET-CP]) commercially available caused irritation. Thirty-one percent volunteers reported slight one hour after application CH-NC-CP, moderate (46% [CH-ET-CP] 23% [commercial product]) severe (8% 69% were described for formulations capsaicinoids. When CH-NC applied to skin, observed only 8% felt which demonstrates utility vehicle. A complementary vitro permeation study showed through epidermal human membrane reduced but prevented nanoencapsulation.