azithromycin + ethambutol

Azithromycin + ethambutol is a **combination of two small molecule antibiotics used as a backbone regimen in the treatment of nontuberculous mycobacterial (NTM) pulmonary infections, particularly Mycobacterium avium complex (MAC) disease**. Azithromycin is a macrolide antibiotic that inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, while ethambutol is a bacteriostatic agent that inhibits arabinosyl transferases involved in cell wall biosynthesis in mycobacteria. This combination is typically used in conjunction with other agents, most notably rifamycins, due to the limited and transient efficacy of azithromycin + ethambutol alone, which is linked to rapid emergence of resistance and poor sustained bacterial kill rates in MAC infection[1]. Azithromycin was developed by Pliva (now Teva), and ethambutol by Lederle Laboratories (now part of Pfizer); both are now produced by multiple generic manufacturers.