Comparative Pharmacology
Head-to-head clinical analysis: ERYTHROMYCIN ETHYLSUCCINATE versus ZMAX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ERYTHROMYCIN ETHYLSUCCINATE versus ZMAX.
ERYTHROMYCIN ETHYLSUCCINATE vs ZMAX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Erythromycin ethylsuccinate is a macrolide antibiotic that binds to the 50S subunit of the bacterial ribosome, inhibiting protein synthesis by blocking translocation of peptidyl-tRNA. It may also have anti-inflammatory and immunomodulatory effects.
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.
400-800 mg orally every 6 hours or 4 times daily; maximum 4 g/day. Intravenous form available but ethylester is oral only.
500 mg orally once daily, administered as a single dose on an empty stomach.
None Documented
None Documented
Terminal elimination half-life: 1.5-2 hours in adults with normal renal function; extended to 5-6 hours in patients with severe hepatic impairment; not significantly altered by renal failure.
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 metabolism and biliary excretion (80-90% as unchanged drug and metabolites into bile); renal excretion accounts for 5-15% of unchanged drug; fecal elimination of unabsorbed drug.
Renal: ~20% unchanged; fecal: ~50% as metabolites; biliary: ~30% as metabolites and parent drug.
Category A/B
Category C
Macrolide Antibiotic
Macrolide Antibiotic