Comparative Pharmacology
Head-to-head clinical analysis: ERYTHROMYCIN AND BENZOYL PEROXIDE versus R P MYCIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ERYTHROMYCIN AND BENZOYL PEROXIDE versus R P MYCIN.
ERYTHROMYCIN AND BENZOYL PEROXIDE vs R-P MYCIN
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.
R-P MYCIN is a macrolide antibiotic that inhibits bacterial protein synthesis by binding to the 50S subunit of the bacterial ribosome, specifically at the 23S rRNA of the peptidyl transferase center. This action blocks the translocation step, thereby preventing the elongation of the peptide chain.
Topical: Apply a thin layer to affected areas once daily in the evening.
Rifampin 600 mg orally once daily or 10 mg/kg intravenously once daily.
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 2-3 hours; prolonged in renal impairment (up to 6-8 hours in anuria).
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 (60-80% unchanged), biliary/fecal (15-20%).
Category A/B
Category C
Macrolide Antibiotic
Macrolide Antibiotic