Comparative Pharmacology
Head-to-head clinical analysis: COTRIM versus RIFAXIMIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: COTRIM versus RIFAXIMIN.
COTRIM vs RIFAXIMIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
COTRIM is a combination of trimethoprim and sulfamethoxazole; sulfamethoxazole inhibits dihydropteroate synthase, and trimethoprim inhibits dihydrofolate reductase, sequentially blocking bacterial folate synthesis.
Rifaximin is a non-aminoglycoside, semi-synthetic antibiotic derived from rifamycin that inhibits bacterial RNA synthesis by binding to the beta-subunit of bacterial DNA-dependent RNA polymerase, thereby blocking transcription.
1 double-strength tablet (160 mg trimethoprim + 800 mg sulfamethoxazole) orally every 12 hours for 5-14 days; 15-20 mg/kg/day (based on trimethoprim) IV divided every 6-8 hours for severe infections.
550 mg orally three times daily for 14 days for travelers' diarrhea; 200 mg orally three times daily for 3 days for irritable bowel syndrome with diarrhea; 400 mg orally three times daily for 7 days for hepatic encephalopathy.
None Documented
None Documented
Clinical Note
moderateRifaximin + Digoxin
"The serum concentration of Digoxin can be increased when it is combined with Rifaximin."
Clinical Note
moderateRifaximin + Levofloxacin
"The serum concentration of Levofloxacin can be increased when it is combined with Rifaximin."
Clinical Note
moderateRifaximin + Estrone sulfate
"The serum concentration of Estrone sulfate can be decreased when it is combined with Rifaximin."
Clinical Note
moderateRifaximin + Tranilast
Sulfamethoxazole: 9-11 hours (normal renal function); trimethoprim: 8-10 hours. Extended in renal impairment (SMX up to 30h, TMP up to 24h).
The terminal elimination half-life is approximately 1.8 to 2.5 hours in patients with normal hepatic function. Due to negligible systemic absorption, the half-life has limited clinical relevance; drug action is largely confined to the gastrointestinal tract.
Renal: 50-70% unchanged sulfamethoxazole, 15-30% N4-acetylated metabolite; trimethoprim: 50-60% unchanged, 10-20% metabolites. Biliary/fecal: minimal.
Rifaximin is primarily eliminated in feces as unchanged drug (>96% of an oral dose). Renal excretion is negligible (<0.4%). Biliary excretion is minimal due to poor systemic absorption.
Category C
Category A/B
Antibiotic
Antibiotic
"The serum concentration of Tranilast can be decreased when it is combined with Rifaximin."