H1-receptor antagonist treatment of seasonal allergic rhinitis

H1-receptor antagonists are usually first-line treatment given for seasonal allergic rhinitis. However, many patients suffer with symptoms of allergic rhinitis rather than tolerate the sedative and anticholinergic side effects of the first-generation H1-receptor antagonists. Researchers have sought to replace these older H1-receptor antagonists with a new generation of H1-receptor antagonists that approach the optimal therapy: clinically effective, safe, free of side effects, and convenient for the patient. Among the new second-generation H1-receptor antagonists are terfenadine and astemizole (already marketed) and loratadine and cetirizine, which are expected to be approved soon. All four demonstrate efficacy, convenience, and minimal side effects on the central nervous system. In this review of the current treatment of seasonal allergic rhinitis, the clinical studies that compare these four new second-generation H1-receptor antagonists are discussed.