Comparative Pharmacology
Head-to-head clinical analysis: NEO RX versus TRIMETHOPRIM SULFATE AND POLYMYXIN B SULFATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NEO RX versus TRIMETHOPRIM SULFATE AND POLYMYXIN B SULFATE.
NEO-RX vs TRIMETHOPRIM SULFATE AND POLYMYXIN B SULFATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Aminoglycoside antibiotic that binds to the 30S ribosomal subunit, causing misreading of mRNA and inhibition of protein synthesis in susceptible bacteria.
Trimethoprim inhibits bacterial dihydrofolate reductase, blocking tetrahydrofolate synthesis and thereby inhibiting thymidine synthesis. Polymyxin B disrupts bacterial cell membrane integrity by binding to lipopolysaccharides in Gram-negative bacteria.
100 mg intravenously every 12 hours.
One drop in each affected eye every 2 to 4 hours for 7 to 10 days.
None Documented
None Documented
Terminal elimination half-life is 2.5-3 hours in adults with normal renal function; increased to up to 10-15 hours in severe renal impairment (CrCl <30 mL/min). Clinically, this supports 8-hourly dosing intervals in normal renal function, with extended intervals in renal impairment.
Trimethoprim: 8-10 hours (normal renal function); Polymyxin B: 6 hours (prolonged in renal impairment).
Renal excretion accounts for 90-100% of elimination, primarily as the parent drug via glomerular filtration and tubular secretion. Urinary excretion: 90-100% unchanged. Fecal/biliary: negligible (<2%).
Trimethoprim: renal (80-90% unchanged, 10-20% metabolites); Polymyxin B: renal (60% unchanged, 40% nonrenal).
Category C
Category D/X
Antibiotic
Antibiotic