Comparative analysis of the sedative effects of mequitazine and other antihistaminic drugs: review of the literature

Abstract

Background: Antihistamines (H 1-receptor antagonists) are widely prescribed to treat symptoms of seasonal and perennial allergic rhinitis and chronic urticaria. Drowsiness and impairment of cognition and psychomotor performance have been reported as adverse events in many trials, and all antihistamines appear to have some sedative properties. Sedation, however, may be a direct result of allergic rhinitis, and the degree of sedation may depend on each individual's response to antihistamine therapy, and thus cannot be predicted. Objective: The purpose of this review was to compare the adverse sedative effects of mequitazine with those of other antihistamines used in clinical practice. Methods: A literature search was conducted to identify all available publications from the MEDLINE ® and Excerpta Medica databases on mequitazine and review articles on nonsedating antihistamine drugs in peer-reviewed journals from 1975 to 1999. Additional publications on mequitazine were provided by the manufacturer of the drug. The clinical outcomes of drowsiness and fatigue in patients with allergic rhinitis were the focus of this comparative analysis. Conclusions: The classification of antihistamines based on their chemical structure alone is misleading. Based on our review of all available product literature on mequitazine and recently published reviews of nonsedating antihistaminic drugs, mequitazine demonstrates a clinically proven low-sedation profile, similar to that seen with current antihistamines, which are frequently reported to be nonsedating. Mequitazine has a low propensity to induce drowsiness, comparable to that of cetirizine and loratadine. Thus, it differs from truly sedative antihistaminic drugs, such as dexchlorpheniramine, which produce drowsiness and fatigue in patients with atopy to a degree that is measurably different from placebo.