Comparative Pharmacology
Head-to-head clinical analysis: ASACOL versus AZULFIDINE EN TABS.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ASACOL versus AZULFIDINE EN TABS.
ASACOL vs AZULFIDINE EN-TABS
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Asacol (mesalamine) is an aminosalicylate that exerts anti-inflammatory effects in the colon via inhibition of prostaglandin and leukotriene synthesis, particularly by blocking cyclooxygenase and lipoxygenase pathways, and by scavenging reactive oxygen species. It also inhibits cytokine production and reduces mucosal inflammation.
Sulfasalazine is a prodrug that is cleaved by colonic bacteria to 5-aminosalicylic acid (5-ASA) and sulfapyridine. 5-ASA inhibits cyclooxygenase and lipoxygenase pathways, reducing prostaglandin and leukotriene synthesis. It also scavenges reactive oxygen species and inhibits NF-κB activation, leading to anti-inflammatory effects.
800 mg orally three times daily or 1600 mg three times daily for 6 weeks; maintenance: 1.6 g daily in divided doses.
500 mg orally twice daily, titrated to 1 g twice daily after 2 weeks for rheumatoid arthritis; 2 g daily in divided doses for ulcerative colitis.
None Documented
None Documented
Terminal half-life: 0.6-1.4 hours for 5-ASA; 6-12 hours for N-acetyl-5-ASA. Clinical context: short t1/2 necessitates multiple daily dosing for sustained colonic exposure.
Sulfapyridine: 12-15 hours (clinical context: dosing interval typically 6-12 hours due to sulfapyridine accumulation; mesalamine: 0.6-1.5 hours, not clinically relevant)
Renal (80% as 5-ASA and N-acetyl-5-ASA), fecal (20%)
Renal (50% as sulfapyridine metabolites, 33% as acetylsulfapyridine, 15% as sulfapyridine glucuronide, 2% as unchanged sulfapyridine; 15-20% as mesalamine metabolites), biliary/fecal (minimal, primarily mesalamine excreted in feces)
Category C
Category C
Aminosalicylate
Aminosalicylate