Comparative Pharmacology
Head-to-head clinical analysis: ERYTHROMYCIN AND BENZOYL PEROXIDE versus ZMAX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ERYTHROMYCIN AND BENZOYL PEROXIDE versus ZMAX.
ERYTHROMYCIN AND BENZOYL PEROXIDE vs ZMAX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Erythromycin is a macrolide antibiotic that acts by binding to the 50S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis. Benzoyl peroxide has bactericidal effects against Propionibacterium acnes, likely through the release of free radical oxygen that oxidizes bacterial proteins. It also has keratolytic and comedolytic properties.
Azithromycin, the active ingredient in ZMAX, is a macrolide antibiotic that binds to the 50S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis and bacterial growth.
Topical: Apply a thin layer to affected areas once daily in the evening.
500 mg orally once daily, administered as a single dose on an empty stomach.
None Documented
None Documented
Erythromycin: 1.4–2.0 hours (terminal half-life in adults). Benzoyl peroxide: Not applicable; it is a topical agent with negligible systemic absorption.
Terminal half-life: 68 hours (range 40-80 h); prolonged in hepatic impairment (up to 120 h) and elderly; supports once-weekly dosing.
Erythromycin is primarily excreted via bile (fecal elimination) with approximately 15% excreted unchanged in urine. Benzoyl peroxide is degraded to benzoic acid, which is conjugated with glycine to form hippuric acid and excreted renally; less than 5% is excreted unchanged in urine.
Renal: ~20% unchanged; fecal: ~50% as metabolites; biliary: ~30% as metabolites and parent drug.
Category A/B
Category C
Macrolide Antibiotic
Macrolide Antibiotic