Comparative clinical studies with ebastine: efficacy and tolerability.

Ebastine is a nonsedating and selective histamine H1 receptor antagonist without anticholinergic or sedative effects at therapeutic doses. It has shown a rapid onset and long duration of action, and doses of 10 and 20mg once daily are effective in relieving the nasal and non-nasal symptoms of seasonal and perennial allergic rhinitis (SAR and PAR, respectively). In 3 randomised double-blind, multicentre clinical trials in patients with SAR, ebastine 10 and 20mg once daily for 2 to 3 weeks significantly reduced symptoms (nasal discharge, stuffiness, sneezing, itchy nose, itchy/watery eyes) when compared with placebo. Similarly, in patients with PAR, two 3-week studies demonstrated that ebastine 10mg twice daily and 20mg once daily significantly relieved the symptoms of PAR, as measured by the Perennial Index. Ebastine was well tolerated in these studies and had no effect on the QTc interval.