Comparative Pharmacology
Head-to-head clinical analysis: ERYC versus ZITHROMAX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ERYC versus ZITHROMAX.
ERYC vs ZITHROMAX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Erythromycin acts by binding to the 50S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis by blocking the translocation step.
Azithromycin is a macrolide antibiotic that binds to the 50S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis by preventing translocation of peptides. It also has immunomodulatory and anti-inflammatory effects.
250-500 mg orally every 6 hours or 333-500 mg orally every 8 hours; maximum 4 g/day.
500 mg orally once daily for 3 days, or 2 g orally as a single dose for certain infections.
None Documented
None Documented
2–4 hours in adults with normal renal function; prolonged to 4–8 hours in severe hepatic impairment; does not significantly change in renal failure.
Terminal elimination half-life of approximately 68 hours (range 35-96 hours), allowing once-weekly dosing for some indications.
Primarily biliary excretion of unchanged drug (60–80%); renal excretion accounts for 10–15% of an oral dose, with minimal fecal elimination (<5%).
Primarily eliminated via biliary/fecal route (∼50-60% as unchanged drug); renal excretion accounts for ∼12% of the dose; minimal metabolism.
Category C
Category C
Macrolide Antibiotic
Macrolide Antibiotic