RESUMEN
To compare the efficacy and safety of the new non-sedating H1 antagonist, Loratadine, with Astemizole, we conducted a double-blind, randomized parallel-group study in 40 allergic rhinitis Thai patients. Following a one-week run-in period, patients who had a mean daily total symptom score of at least 6 were randomized to study treatment. Twenty received Loratadine, the other 20 received Astemizole in the same dosage i.e., 10 mg tablet once a day for two weeks. The daily symptom scores recorded by the patients and the weekly symptom scores recorded by the physicians showed similar significant reductions in all symptoms. Both treatments were well-tolerated and no major adverse events were reported. However, drowsiness happened more frequently in the Astemizole group and the onset of relief in the Loratadine group was more rapid. Patients’ ratings for treatment efficacy in both groups were not significantly different. We conclude that both Loratadine and Astemizole taken 10 mg once a day are equally effective in reducing allergic rhinitis symptoms. But Loratadine appears to cause less sedation and to offer more rapid onset of relief.