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


CONCLUSIONS
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.
Salmun
L M
LM
Schering-Plough Corporation, Kenilworth, New Jersey 07033, USA.
Gates
D
D
Scharf
M
M
Greiding
L
L
Ramon
F
F
Heithoff
K
K
D000328:Adult; D018926:Anti-Allergic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D017332:Cetirizine / Q000009:adverse effects* / Q000627:therapeutic use; D006970:Disorders of Excessive Somnolence / Q000139:chemically induced*; D004311:Double-Blind Method; D004526:Efficiency / Q000187:drug effects; D005260:Female; D006634:Histamine H1 Antagonists / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D017336:Loratadine / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D009042:Motivation; D012221:Rhinitis, Allergic, Perennial / Q000188:drug therapy; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy; D014937:Work
D018926:Anti-Allergic Agents; D006634:Histamine H1 Antagonists; D017336:Loratadine; D017332:Cetirizine