Inhibition of acute lung anaphylaxis by aerosolized azelastine in guinea pigs sensitized by three different procedures.

The influence of aerosolized azelastine on acute lung anaphylaxis in actively sensitized guinea pigs (experimental asthma model) was studied. Azelastine administered as an aerosol produced significant inhibition of acute lung anaphylactic responses, ie, the reduction in dynamic lung compliance and an increase in pulmonary airway resistance. These data showed that regardless of the method of sensitization and time of administration (immediately or 15 minutes before antigen challenge), aerosolized azelastine affords significant protection against acute lung anaphylaxis. The inhibition of acute lung anaphylaxis by aerosolized azelastine in the guinea pig asthma model may be due to (1) inhibition of the synthesis/release of chemical mediators, eg, histamine and leukotrienes, etc and/or (2) antagonism of the pharmacologic mediators at the receptor site in respiratory smooth muscles.