Comparative Pharmacology
Head-to-head clinical analysis: GENTAFAIR versus NEOMYCIN AND POLYMYXIN B SULFATES AND BACITRACIN ZINC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: GENTAFAIR versus NEOMYCIN AND POLYMYXIN B SULFATES AND BACITRACIN ZINC.
GENTAFAIR vs NEOMYCIN AND POLYMYXIN B SULFATES AND BACITRACIN ZINC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Gentamicin is an aminoglycoside antibiotic that binds to the 30S ribosomal subunit of susceptible bacteria, inhibiting protein synthesis and causing misreading of mRNA, leading to cell death.
Neomycin is an aminoglycoside that binds to the 30S ribosomal subunit, causing misreading of mRNA and inhibition of protein synthesis. Polymyxin B is a polypeptide that disrupts bacterial cell membrane permeability by interacting with phospholipids. Bacitracin inhibits bacterial cell wall synthesis by interfering with dephosphorylation of the lipid carrier in peptidoglycan biosynthesis.
Gentamicin 3-5 mg/kg IV or IM once daily for serious infections; alternatively, 1.5-2 mg/kg IV or IM every 8 hours.
Apply thin layer to affected area 2-3 times daily. For ophthalmic use: 1-2 drops in affected eye every 4 hours, or 1/2 inch ribbon of ointment in conjunctival sac 2-3 times daily.
None Documented
None Documented
2-3 hours (normal renal function); may extend to 24-48 hours in severe renal impairment, necessitating dose adjustment.
Neomycin: 2-3 h (terminal), prolonged in renal impairment; polymyxin B: 6-7 h (terminal), extended in renal failure; bacitracin: 1.5 h (if absorbed), not clinically relevant due to minimal absorption.
Renal: over 90% unchanged via glomerular filtration; minor biliary (<1%).
Renal: ~90% of absorbed neomycin and polymyxin B; bacitracin zinc: minimal systemic absorption, excreted primarily in feces. For neomycin: ~99% fecal after oral; polymyxin B: ~60% renal, rest biliary; bacitracin: nearly 100% renal if absorbed.
Category C
Category A/B
Aminoglycoside Antibiotic
Aminoglycoside Antibiotic