Second-generation H1-receptor antagonists

Abstract

The second-generation H1-receptor antagonists do not penetrate into the central nervous system as readily as the first-generation H1-receptor antagonists do. They bind preferentially to peripheral rather than central H1-receptors. They cause no more sedation than placebo does. These medications differ considerably from one another in some aspects of basic pharmacology and in pharmacokinetics and pharmacodynamics. An understanding of these differences will facilitate their optimal clinical usage. The second-generation H1-receptor antagonists are replacing the first generation H1-receptor antagonists in the symptomatic treatment of allergic rhinoconjunctivitis, and in relieving pruritus in patients with urticaria. They have a mild beneficial effect in patients with chronic asthma. They have not supplanted the first generation H1-receptor antagonists in atopic dermatitis treatment or as adjunctive treatment of pruritus and other symptoms in patients with anaphylaxis.