Loratadine versus cetirizine: assessment of somnolence and motivation during the workday.

Abstract Objective This parallel-group, double-blind study compared the somnolence and motivation profiles of 2 second-generation antihistamines, loratadine and cetirizine, in patients with allergic rhinitis. Background Second-generation antihistamines were developed to provide symptomatic relief from allergic disorders without the unwanted side effects of first-generation antihistamines, including somnolence. Recent research has indicated that not all secondgeneration antihistamines are comparable with respect to somnolence and other cognitive processes. Methods Patients aged ≥ 12 years and actively exhibiting symptoms of allergic rhinitis were randomized to 2 treatment groups to receive 10 mg loratadine or 10 mg cetirizine daily at 8:00 am for 1 week. After patients took the medication, their somnolence and degree of motivation to perform activities were recorded in an electronic diary using a visual analog scale 4 times dunng the workday (8:00 am , 10:00 am , noon, and 3:00 pm ). Results Sixty patients (31 men, 29 women) were randomized to treatment. Somnolence scores were similar for both groups at baseline and at the time of dosing (8:00 am ). However, there was a statistically significant difference in somnolence scores between the loratadine and cetirizine groups at 10:00 am ( P = 0.008), noon ( P = 0.001), and 3:00 pm ( P am measurements. In parallel with the somnolence scores, there were statistically significant differences in motivation scores between the loratadine and cetirizine groups at 10:00 am ( P = 0.014), noon ( P = 0.001), and 3:00 pm ( P Conclusion The results of this study demonstrate that in patients aged ≥12 years who had allergic rhinitis, cetirizine use promoted somnolence and decreased motivation to perform activities during the workday compared with loratadine.