Azithromycin belongs to the macrolide class of antibiotics and is commonly used clinically to treat infections such as chlamydia and mycoplasma.Other antibiotics that can also be used to treat chlamydia and mycoplasma infections are macrolides such as roxithromycin, erythromycin, and dirithromycin, tetracyclines such as minocycline, fenoldones such as ofloxacin, moxifloxacin, and cetafloxacin, and third-generation cephalosporins such as cephalexin, cefdinir, and fosfomycin etc. Chlamydia is a group of very small, non-motile, microorganisms that grow exclusively within cells, and can be categorized into Chlamydia pneumoniae, Chlamydia psittaci, Chlamydia trachomatis, and Chlamydia bovis, with Chlamydia pneumoniae and Chlamydia trachomatis being the more common ones. Chlamydia pneumoniae is considered a common cause of pneumonia bronchitis and other respiratory infections, and Chlamydia trachomatis, in addition to causing trachoma, is also recognized as one of the infectious agents of sexually transmitted diseases, and should therefore be treated aggressively.