Mesalamine
Mesalamine. Active anti-inflammatory metabolite of sulfasalazine — local action in colon mucosa via COX/LOX inhibition + scavenging of reactive oxygen species.…
Active anti-inflammatory metabolite of sulfasalazine — local action in colon mucosa via COX/LOX inhibition + scavenging of reactive oxygen species. First-line for mild-to-moderate ulcerative colitis; pH- and time-controlled formulations target distal ileum/colon.
PK REMOVED. THE SHAPE CANNOT BE FIXED, NOT MERELY THE NUMBERS. Against its own citation the observed peak-to-exposure ratio is 0.283 per hour while the model CEILING at that paper own peak time is 0.042 — 6.8x OUTSIDE WHAT ANY ABSORPTION RATE CAN PRODUCE — because the real profile is a delayed-release lag followed by fast absorption, which is what a colonic tablet is. At the registry own minimum dose the stored parameters over-predicted exposure 6.8x and peak 6.0x against verbatim measurements. A single bioavailability is also indefensible across the delivery systems this dose range spans: two pH-dependent tablets differ 8.5-fold per milligram, and the mechanism is stated verbatim — "pH-dependent mesalazine formulations may release their contents rapidly in the small intestine and proximal colon resulting in higher plasma and urinary concentrations". THE STORED BIOAVAILABILITY WAS ALSO THE SULFASALAZINE RECORD CITATION SPEAKING: "at least 25% is absorbed" is an inequality about colonic 5-aminosalicylate after azo-cleavage, not a tablet systemic availability. Effect is luminal by its own literature — "its mode of action appears to be TOPICALLY rather than systemically" — and a plasma curve here is a nephrotoxicity index, not an efficacy one.
Sources: PMID:8141827, PMID:15142198, PMID:3319458