Zmax (Pfizer)

Azithromycin sustained release (SR), marketed under the brand name Zmax, is a macrolide antibiotic developed by Pfizer for the treatment of mild to moderate community-acquired pneumonia (CAP) and acute bacterial sinusitis. Unlike traditional azithromycin regimens that require multiple days of dosing, Zmax is formulated as a single 2.0-gram oral dose using a microsphere-based delivery system. This technology allows for the slow release of the active ingredient in the small intestine, achieving high systemic exposure while reducing the gastrointestinal side effects typically associated with high-dose immediate-release macrolides. The drug exerts its antibacterial effect by binding to the 50S ribosomal subunit of susceptible bacteria, specifically the 23S rRNA, thereby inhibiting RNA-dependent protein synthesis and bacterial growth.

Brand names

Zmax

Other names

azithromycin sustained releaseazithromycin SRazithromycin extended release