[New drugs in the treatment of respiratory allergic diseases].
The drugs recently available for the treatment of allergic respiratory diseases include: 1) topical steroids as fluticasone and budesonide; 2) nasal and ocular sodium nedocromil; 3) nasal N-acetyl-aspartyl-glutamic acid; 4) topical antihistamines as levocabastine and azelastine; 5) antileukotrienes and anti PAF (experimental). Topical steroids are the most effective drugs; the new molecules have a low gastric absorption and a rapid liver-metabolism which decreases the risks of systemic side effects. In the treatment of allergic conjunctivitis ocular sodium nedocromil seems to be more effective than cromoglycate, however further studies are needed to evaluate the effectiveness of the nedocromil nasal formulation. In allergic rhinitis good clinical results are obtained using NAAGA. In the treatment of allergic rhino-conjunctivitis topical antihistamines seem as effective as the antihistamines administered by oral route; moreover they cause less side effects. The anti-leukotrienes drugs can be used in the treatment of moderate asthma. In the treatment of bronchial asthma no clinical and functional improvement has been reported using PAF or thromboxane A2 receptor antagonists.