Objective antihistamine side effects are mitigated by evening dosing of hydroxyzine.

First-generation antihistamines have potency, pharmacokinetic, and cost advantages compared with nonsedating second-generation antihistamines. Bedtime dosing of hydroxyzine was investigated as a dosing strategy to minimize reaction time degradation and adverse subjective symptoms previously documented for hydroxyzine in divided doses. Hydroxyzine, 50 mg qhs, was compared with terfenadine, 60 mg bid, in this double-blind, placebo-controlled crossover study of 15 healthy, asymptomatic adults.

The relationships between late cutaneous responses and specific antibody responses with outcome of immunotherapy for seasonal allergic rhinitis.

Mountain cedar (MC) (Juniperus ashei) causes a significant and isolated seasonal allergic rhinitis in south-central Texas during the winter months. Retrospective studies have indicated that patients segregate into two categories based on skin test reactions: single positive skin test to MC only and multiple positive skin tests. These two populations differed in age, personal and family history of atopy, levels of both IgE and total MC-specific IgE (sIgE), and symptomatology.