LORATADINE TREATMENT OF RHINITIS DUE TO POLLEN ALLERGY REDUCES EPITHELIAL ICAM-1 EXPRESSION

Background Loratadine and cetirizine are new generation antihistamines , which are clinically effective in the treatment of allergic rhinitis . Objective The aim of the study was to evaluate antiallergic activity of loratadine compared with cetirizine, over a 2 week period under na tural allergen exposure, in a double-blind parallel groups, randomized , controlled trial. Methods Twenty patients, sensitized to grass and/o r Parietaria pollen, were subdivided into two groups, one receiving lo ratadine the other cetirizine respectively. Both were dosed at 10 mg/d ay. Evaluated parameters were: clinical symptoms, nasal inflammatory c ell (such as neutrophil, eosinophil and metachromatic cells) counts, I CAM-1 expression on nasal epithelial cells, and nasal mediators (e.g. histamine, ECP, EPO and MPO). Results Loratadine and cetirizine signif icantly improved symptoms (P < 0.002), significantly reduced eosinophi l (P < 0.016) and metachromatic cell (P < 0.01) infiltration, levels o f ECP (P < 0.002), EPO (P < 0.006) and histamine (P < 0.01) and ICAM-1 expression on nasal epithelial cells (P < 0.02). No difference was de monstrated between the two drugs. Conclusion The antiallergic activity of loratadine and cetirizine is documented by their actions on the in flammatory and clinical parameters, especially ICAM-1 modulation.