Comparative Pharmacology
Head-to-head clinical analysis: TERRAMYCIN POLYMYXIN versus TERRAMYCIN W POLYMYXIN B SULFATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: TERRAMYCIN POLYMYXIN versus TERRAMYCIN W POLYMYXIN B SULFATE.
TERRAMYCIN-POLYMYXIN vs TERRAMYCIN W/ POLYMYXIN B SULFATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Terramycin (oxytetracycline) inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit, preventing aminoacyl-tRNA attachment. Polymyxin disrupts bacterial cell membrane permeability by binding to lipopolysaccharides, leading to cell death.
Oxytetracycline: inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit, blocking aminoacyl-tRNA binding. Polymyxin B sulfate: disrupts bacterial cell membrane permeability by binding to lipopolysaccharides in Gram-negative bacteria.
Adults: 1-2 drops into affected eye(s) every 4 hours, or 1/2-1 inch ribbon of ointment into conjunctival sac 3-4 times daily. For dermatological use: apply sparingly to affected area 2-3 times daily.
1-2 g oxytetracycline (as hydrochloride) plus 100,000-250,000 units polymyxin B sulfate IM every 8-12 hours (deep IM only); ophthalmic: 1-2 drops suspension every 4-6 hours; topical: apply thin layer to affected area 2-4 times daily.
None Documented
None Documented
Terramycin: 6-10 hours (prolonged in renal impairment); polymyxin B: 6-7 hours (prolonged in renal impairment); clinical context: dosing interval adjustment required for renal dysfunction
Oxytetracycline: terminal elimination half-life is 6-10 hours in patients with normal renal function; extends to 48-60 hours in severe renal impairment. Polymyxin B: terminal half-life is 6-8 hours in normal renal function; prolonged to 2-3 days in anuria.
Renal (terramycin: ~70% unchanged in urine; polymyxin B: ~60% unchanged in urine), biliary/fecal (terramycin: ~20-30% in feces; polymyxin B: ~40% fecal elimination)
Approximately 60% of oxytetracycline is excreted unchanged in the urine via glomerular filtration; 20-30% is eliminated in feces via biliary secretion. Polymyxin B is primarily eliminated by renal tubular secretion, with about 60% of a parenteral dose recovered unchanged in urine within 24 hours; minor fecal elimination.
Category C
Category C
Topical Antibiotic Combination
Topical Antibiotic Combination