Comparative Pharmacology
Head-to-head clinical analysis: E E S versus ZMAX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: E E S versus ZMAX.
E.E.S. vs ZMAX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Erythromycin (E.E.S.) binds to the 50S subunit of bacterial ribosomes, inhibiting peptide chain elongation and protein synthesis. It also exhibits prokinetic effects on the gastrointestinal tract via motilin receptor agonism.
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.
250-500 mg every 6 hours orally or 15-20 mg/kg/day IV divided every 6 hours.
500 mg orally once daily, administered as a single dose on an empty stomach.
None Documented
None Documented
1.5-2 hours in adults with normal renal function; prolonged to 4-6 hours in patients with hepatic impairment; may be shorter in children.
Terminal half-life: 68 hours (range 40-80 h); prolonged in hepatic impairment (up to 120 h) and elderly; supports once-weekly dosing.
Primarily hepatic (biliary) excretion of unchanged drug and active metabolites; approximately 15% of an oral dose is excreted unchanged in urine. The remainder is eliminated via feces as unchanged drug and metabolites.
Renal: ~20% unchanged; fecal: ~50% as metabolites; biliary: ~30% as metabolites and parent drug.
Category C
Category C
Macrolide Antibiotic
Macrolide Antibiotic