Ebastine - An update of its use in allergic disorders

Ebastine is a second-generation antihistamine which undergoes transformation to its active metabolite, carebastine. Its antihistaminic and antiallergic effects have been demonstrated in in vitro and in vivo studies, in addition to data obtained from clinical trials. Patients with allergic rhinitis or chronic idiopathic urticaria experienced significant improvement in their symptoms with ebastine 10 or 20mg once daily. Some studies in patients with seasonal allergic rhinitis (SAR) have indicated trends towards greater efficacy with the 20mg than the 10mg dose, although only 1 study has shown statistically significant benefits. In comparative trials in patients with SAR, ebastine 10mg was as effective as most other second-generation antihistamines, including astemizole, azelastine, cetirizine, loratadine and terfenadine. Ebastine 20 mg/day was significantly superior to loratadine 10 mg/day in patients with SAR according to effects on secondary efficacy variables in comparative studies; 1 study found significantly greater changes from baseline in mean total symptom score with ebastine 20mg (-43 vs -36% with loratadine, p = 0.035). In patients with perennial allergic rhinitis, ebastine 10 or 20mg daily was significantly more effective than loratadine in reducing total symptom scores from baseline in 1 comparative study. There have been no reports of serious adverse cardiac effects during ebastine therapy. Increases in corrected QT interval have been observed during clinical trials; however, these have not been considered clinically significant and were generally of similar magnitude to those seen with loratadine. The normal diurnal variation in QTc interval and the problems associated in correcting for changes in heart rate also complicate assessment of this issue. The incidence of adverse events during ebastine treatment is not significantly greater than that observed with placebo or other second-generation antihistamines. Conclusions: Ebastine 10mg daily is a well tolerated and effective treatment for allergic rhinitis and chronic idiopathic urticaria. At this dosage, it is as effective as the other second-generation antihistamines against which it has been compared. Ebastine 20mg has similar tolerability to the 10mg dose, and trends towards greater efficacy with the higher dose have been shown in some studies. Ebastine does not appear to be associated with any significant cardiac adverse events. Ebastine is a useful treatment option fur patients with allergic rhinitis or chronic idiopathic urticaria.