Efficacy and safety of cetirizine in allergic diseases. Results of a multicenter study in 1,251 patients

In an open multicenter study, the clinical efficacy and tolerability of the non-sedating H1-receptor antagonist cetirizine was studied in 1,251 patients. The study was undertaken under outpatient condition and in collaboration with 133 doctors in Austria during the pollen season. The included patients, 45% males and 55% females, aged 6-90 years (mean 32 ± 18 years) suffered from seasonal allergic rhinitis i.e. allergy of the respiratory airways (828 patients, 66.2%), allergic urticaria (319 patients, 25.5%) and both allergies (104 patients, 8.3%). 65% of all patients were pretreated with other drugs such as corticosteroids, local therapies, inhalative, beta-mimetics, bronchodilatators etc. During the treatment of a 4 week period, patients received a single dose of cetirizine 10 mg once a day (children < 30 kg received 5 mg). The efficacy of cetirizine was assessed according to a 4-point-rating scale. 13 different symptoms of the allergy were evaluated. Overall, a consistent and significant reduction (p < 0,0001) of all symptoms, i.e. itching of the nose and eyes, sneezing, runny nose, nose obstruction, various forms of urticaria and in asthma was achieved. The improvement was obviously achieved after 1 week of treatment. A total normalization was detected after 3 weeks of treatment. However, the urticaria reactions were abolished 4-6 hours after administration of the drug. The average severity and recovery of each symptom was similar throughout the treatment groups. Cetirizine was effective in 91.6% of all patients and was well tolerated by most patients. Only 3% showed no efficacy. No severe adverse events were reported in patients taking cetirizine. In only 5.7% (71 patients) mild to moderate adverse events occurred in this study and affected all ages and both sexes. These results suggest that cetirizine is very effective in the control and treatment of seasonal allergic rhinitis, allergic urticaria and is also beneficial in the treatment of hay fever with concomitant asthma. It reduces significantly the symptoms and the duration of symptoms in allergies.