Comparative Pharmacology
Head-to-head clinical analysis: DIFICID versus TRIMETHOPRIM SULFATE AND POLYMYXIN B SULFATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DIFICID versus TRIMETHOPRIM SULFATE AND POLYMYXIN B SULFATE.
DIFICID vs TRIMETHOPRIM SULFATE AND POLYMYXIN B SULFATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Fidaxomicin is a macrocyclic antibiotic that inhibits bacterial RNA polymerase, leading to RNA synthesis inhibition and cell death. It is bactericidal against Clostridioides difficile and has minimal systemic absorption.
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.
200 mg (tablet) orally twice daily for 10 days.
One drop in each affected eye every 2 to 4 hours for 7 to 10 days.
None Documented
None Documented
11.7 hours (terminal half-life in healthy subjects); supports twice-daily dosing.
Trimethoprim: 8-10 hours (normal renal function); Polymyxin B: 6 hours (prolonged in renal impairment).
Fecal (primarily as unchanged drug, ~44% of dose); renal (~1.6% unchanged, <1% as metabolites); biliary (minor).
Trimethoprim: renal (80-90% unchanged, 10-20% metabolites); Polymyxin B: renal (60% unchanged, 40% nonrenal).
Category C
Category D/X
Antibiotic
Antibiotic