Antihistamines added to an antileukotriene in treating seasonal allergic rhinitis: Histamine and leukotriene antagonism

Cysteinyl leukotrienes (CysLTs) are a key element of allergic inflammation. Thus, the antagonism of CysLTs appears a potential target of allergic rhinitis management. Antileukotrienes and antihistamines combined showed a synergistic effect in treating seasonal allergic rhinitis (SAR). This double blind, parallel group, randomized study aimed at evaluating the clinical and anti-inflammatory effects exerted by two combinations of antihistamine plus antileukotriene in patients with SAR and mild intermittent asthma. Thirty patients were treated with montelukast added to cetirizine (M-C group) or desloratadine (M-D group) for 2 weeks. The visits, including spirometry, nasal scraping and lavage, were performed in all subjects before and directly after the treatment. Evaluation parameters were: i) nasal symptoms, ii) number of eosinophils and neutrophils, and iii) IL5 and IL8 levels. Both combinations significantly reduced: nasal symptoms (p