balsalazide

Balsalazide is an aminosalicylate prodrug used to treat inflammatory bowel disease, primarily ulcerative colitis. It consists of 5-aminosalicylic acid (5-ASA) bound to a carrier via an azo bond. In the colon, bacterial azoreductases cleave the azo linkage, releasing active 5-ASA and a benign carrier fragment. The design aims to deliver 5-ASA directly to the inflamed mucosa with limited systemic absorption.

Medical uses: Indicated for active mild-to-moderate ulcerative colitis and for maintenance to prevent relapse in patients who respond to therapy; not routinely used for Crohn's disease unless there is colonic involvement. It may be prescribed when a lower systemic exposure to mesalamine is desired compared to some other formulations.

Pharmacology: Mechanism is anti-inflammatory; 5-ASA inhibits inflammatory mediators, scavenges free radicals, and modulates NF-kB signaling in colonic mucosa. Systemic absorption is low; most activity occurs locally in the colon.

Administration and dosing: Administered orally, typically in divided doses with meals. Balsalazide is available as 750 mg capsules (brand Colazal) and generic equivalents; total daily dose is tailored to disease severity and response, often several capsules per day; maintenance doses may be reduced after remission.

Safety: Common adverse effects include headache, abdominal pain, nausea, diarrhea, and flatulence. Less frequent reactions include hypersensitivity, rash, pancreatitis, and kidney function impact. It can interact with other salicylates or mesalamine-containing products, increasing the risk of adverse effects. Contraindicated in known hypersensitivity to balsalazide or salicylates; used with caution in renal impairment, active gastrointestinal ulcers, or severe dehydration. Pregnancy risk should be discussed with a clinician.