Mesalazine (5-aminosalicylic acid or 5-ASA) is an anti-inflammatory drug used primarily for the treatment of mild to moderate ulcerative colitis. It acts topically on the colonic mucosa to reduce inflammation. The 1200mg strength is typically formulated as a delayed-release tablet designed for once-daily dosing, improving patient compliance. It is a first-line maintenance therapy for ulcerative colitis in remission.
Adult: For maintenance of remission in ulcerative colitis: 1.2g to 2.4g once daily. For induction of remission: 2.4g to 4.8g per day in divided doses. The 1200mg tablet is often used as a once-daily (1 tablet) or twice-daily (2 tablets) regimen depending on clinical need.
Note: Swallow the delayed-release tablet whole with a full glass of water. Do NOT crush, break, or chew. Can be taken with or without food, but consistency in timing with respect to meals is advised. Take the dose at the same time each day.
Mesalazine's exact mechanism is not fully elucidated but is primarily a topical anti-inflammatory agent. It acts locally on the colonic and rectal mucosa to inhibit multiple pathways in the arachidonic acid cascade, reducing the synthesis of pro-inflammatory prostaglandins and leukotrienes. It also scavenges reactive oxygen species and inhibits neutrophil chemotaxis and function.
Pregnancy: Pregnancy Category B (US FDA). Considered relatively safe. Extensive experience in pregnant women with IBD. Use if clearly needed. Benefits generally outweigh risks. Monitor disease activity closely.
Driving: No known effects on driving ability. Dizziness has been reported rarely.
| Azathioprine / 6-Mercaptopurine | Concurrent use may increase risk of blood dyscrasias (leukopenia, pancytopenia). | Major |
| Warfarin | Mesalazine may potentiate the anticoagulant effect, increasing INR and bleeding risk. | Moderate |
| Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) e.g., Ibuprofen, Diclofenac | May increase risk of nephrotoxicity (additive renal effects). | Moderate |
| Lactulose | May lower colonic pH and potentially reduce the release of mesalazine from pH-dependent formulations. | Moderate |
| Thioguanine | Increased risk of myelosuppression. | Major |
| Probiotics | No significant interaction, often used adjunctively. | Minor |