Comparative Pharmacology
Head-to-head clinical analysis: TRIMETHOPRIM versus XIFAXAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: TRIMETHOPRIM versus XIFAXAN.
TRIMETHOPRIM vs XIFAXAN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Trimethoprim inhibits bacterial dihydrofolate reductase (DHFR), preventing the reduction of dihydrofolate to tetrahydrofolate, thereby inhibiting thymidine synthesis and bacterial DNA replication. It has bacteriostatic activity against susceptible organisms.
Rifaximin is a non-systemic, gut-selective antibiotic that inhibits bacterial RNA synthesis by binding to the beta-subunit of bacterial DNA-dependent RNA polymerase, thereby reducing bacterial overgrowth and altering gut microbiota composition.
Adult: 100 mg orally twice daily or 200 mg once daily for uncomplicated UTI; for severe infections, up to 20 mg/kg/day in divided doses. IV: 10-20 mg/kg/day divided every 6-12 hours.
550 mg orally twice daily for traveler's diarrhea; 550 mg orally three times daily for hepatic encephalopathy.
None Documented
None Documented
Clinical Note
moderateTrimethoprim + Teriflunomide
"The metabolism of Teriflunomide can be decreased when combined with Trimethoprim."
Clinical Note
moderateTrimethoprim + Sulfisoxazole
"The metabolism of Sulfisoxazole can be decreased when combined with Trimethoprim."
Clinical Note
moderateTrimethoprim + Cyclosporine
"The metabolism of Cyclosporine can be decreased when combined with Trimethoprim."
Clinical Note
moderateTrimethoprim + Fluconazole
Terminal elimination half-life is 8-12 hours in adults with normal renal function; prolonged to 20-40 hours in severe renal impairment (CrCl <15 mL/min).
The terminal elimination half-life for rifaximin after oral administration ranges from 1.8 to 10 hours, with a mean of approximately 6 hours. The half-life is extended in hepatic impairment due to reduced clearance, and no dosage adjustment is recommended for renal impairment.
Renal excretion: approximately 50-60% of the dose is excreted unchanged in urine via glomerular filtration and tubular secretion; about 10-20% as metabolites (conjugated and oxidized forms); biliary/fecal excretion accounts for less than 10%.
Rifaximin is primarily eliminated unchanged in feces via biliary excretion (approximately 97% of an oral dose). Renal excretion of unchanged drug accounts for <0.4% of the dose. Fecal elimination is the major route.
Category D/X
Category C
Antibiotic
Antibiotic
"The metabolism of Fluconazole can be decreased when combined with Trimethoprim."