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Loratadine versus cetirizine: assessment of somnolence and motivation during the workday
L M Salmun1, D Gates, M Scharf
1Schering-Plough Corporation, Kenilworth, New Jersey 07033, USA.
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 second-generation antihistamines are comparable with respect to somnolence and other cognitive processes.
Methods:
Patients aged > or = 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 during 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 < 0.001), with the cetirizine group showing a greater degree of somnolence. The scores on motivation to perform activities were similar for both groups at the baseline and 8:00-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 < 0.001), indicating that patients taking loratadine were relatively more motivated during the workday.
Conclusion:
The results of this study demonstrate that in patients aged > or = 12 years who had allergic rhinitis, cetirizine use promoted somnolence and decreased motivation to perform activities during the workday compared with loratadine.
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