clarithromycin + ethambutol

Clarithromycin + ethambutol is a combination of two small-molecule antibiotics used primarily for the treatment of Mycobacterium avium complex (MAC) pulmonary disease. Clarithromycin is a macrolide antibiotic that inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, while ethambutol is an antimycobacterial agent that inhibits arabinosyl transferases involved in cell wall biosynthesis. This combination regimen has been studied as an alternative to the standard three-drug therapy (clarithromycin, ethambutol, and rifampicin), particularly when rifampicin cannot be used due to drug interactions or adverse effects. Clinical studies suggest that clarithromycin plus ethambutol may be similarly effective as the three-drug regimen for MAC lung disease and may have a lower incidence of adverse events leading to discontinuation. The primary indication is nontuberculous mycobacterial infections, especially MAC pulmonary disease.