Objective: The aim of the study was to compare the effect of inhibition skin reactivity after administration of single dose administration of various second generation antihistamines in the healthy people group.
Material and methods: Forty two healthy subjects (aged 22+/-18 years) were randomized into seven groups which received orally: cetirizine 10 mg, loratadine 10 mg, desloratadine 5 mg, levocetirizine 5 mg, fexofenadne 120 mg and 180 mg, or placebo respectively. The skin microcirculation reaction after 10 mg/ml histamine administration was estimated visually on the forearm (diameter of wheal and flare) and by Laser Doppler flowmetry before and after study drug or placebo administration prior and, 2, 4, 6, 8, 10, 12, 18, 24 h and one time daily every next 9 days.
Results: There were significant differences of histamine-induced wheal, flare and skin blood flow inhibition vs baseline and placebo after drug administration. There were different dyr'mmics in suppression effect after histamine-induced skin reactivity in various drug groups. The overall inhibitory potency was statistically higher for cetirizine, levocetirizine and fexofenadine (even 95% ve basline) as compared to loratadine and desloratadine (even 65% vs basline). Different times of retreated inhibition effect after administered drugs were observed.
Conclusions: The study drugs shown significant different dynamics of skin reaction inhibition vs baseline and placebo. There were observed strongest effect after levocetirizine and cetirizine and next order after fexofenadine, desloratadine and loratadine.