Azithromycin and lower respiratory tract infections.

Azithromycin is a macrolide antibiotic that has been structurally modified from erythromycin with an expanded spectrum of activity and improved tissue pharmacokinetic characteristics relative to erythromycin. This allows once-daily administration for 3-5 days of treatment compared with traditional multi dosing 7-10-day treatment regimens. It has been successfully employed in lower respiratory tract infections. Recent data indicate that azithromycin may exert anti-inflammatory/immunomodulatory effects that may be of use in the treatment of both acute and chronic airway diseases. This review examines the role of azithromycin in lower respiratory tract infections analysing published data on exacerbations of chronic bronchitis, community-acquired pneumonia and cystic fibrosis both in adults and children. In addition, pharmacokinetic and pharmacodynamic properties of the drug are also considered.