Azithromycin—a new macrolide

Azithromycin is a macrolide derivative referred to as an azalide. It was approved for clinical use in 1992 and has several advantages over traditional macrolides such as erythromycin. Azithromycin is more acid stable and therefore has greater oral bioavailability. It has a longer half life and thus can be administered once daily. Azithromycin also achieves higher tissue concentrations and enhanced antimicrobial activity compared with erythromycin. Finally, azithromycin has a lower incidence of adverse side effects and drug interactions than other macrolides. In obstetrics and gynecology, azithromycin is of primary value for treatment of respiratory tract infections and chlamydial infections.