Pruritus (itching) is one of the major features of eczema, with the associated scratching leading to excoriated, often superinfected, lesions as well as bleeding, lichenification (thickened and leathery skin) or nodular changes. Pruritus can also cause significant sleep deprivation, affecting the patient’s and family’s quality of life.
Systemic antihistamines and anxiolytics may be useful through their sedating effects; dosing at bedtime can avoid daytime drowsiness. Diphenhydramine (Benadryl) and hydroxyzine (Atarax) are most commonly used with excellent safety profiles and therapeutic effects. Doxepin, a tricyclic antidepressant that is a histamine H1- and H2- receptor antagonist, may be given at a dose of 10 to 50 mg. once in the evening, although it is generally reserved for severe patients.
Second-generation antihistamines have been less useful in atopic dermatitis, especially in controlling pruritus, but they may benefit patients with allergic triggers. In a large study of young children with atopic dermatitis, treatment with cetirizine was shown to reduce the number developing asthma in the subgroups sensitized to house dust mites or pollen.