There is no evidence to support the effectiveness of expensive nonsedating agents.
Large, randomized, double-blind, placebo-controlled clinical trials with definitive conclusions (grade A trials) have not been performed.
Two grade B trials (small, rigorous, randomized trials with uncertain results due to moderate to high α or β error) refuted the use of antihistamines in relieving pruritus.
One grade B trial supported the efficacy of antihistamines in relieving pruritus.
All remaining trials (grade C) lacked placebo controls or randomization, or contained fewer than 20 patients in each treatment group.
The itch-scratch cycle exacerbates damage to the epidermal barrier thereby increasing water loss and drying, which creates a suitable environment for skin pathogens to cause infection and flaring of symptoms.
Despite the frequent use of histamine H receptor antihistamines in managing pruritus in atopic dermatitis, few randomized, double-blind, placebo-controlled clinical studies have evaluated efficacy.
In addition to older sedating formulations, expensive nonsedating agents are sometimes used in the absence of any clinical evidence that demonstrates relief of pruritus.
Although antihistamines are often used in the treatment of atopic dermatitis, little objective evidence exists to demonstrate relief of pruritus.
The majority of trials are flawed in terms of the sample size or study design.