Pentasa Mesalazine Prolonged‑release Tablets

1. Indications and Usage
Ulcerative Colitis: Indicated for the induction of remission and for the maintenance of remission in patients with mild-to-moderate ulcerative colitis.
Distal Disease: Particularly effective for involvement of the rectum and left-sided colon.
2. Dosage and Administration
Adults (Induction): The usual starting dose is 1.6 g daily, administered in divided doses (e.g., 800 mg twice daily or 400 mg four times daily).
Maintenance: Once remission is achieved, the maintenance dose is typically 1.6 g daily.
Administration: Tablets should be swallowed whole with liquid and should not be crushed or chewed, to preserve the prolonged-release mechanism.
3. Mechanism of Action
Anti-inflammatory: Mesalazine acts locally in the colonic mucosa to inhibit the cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism.
Scavenging: It scavenges reactive oxygen species and inhibits the release of inflammatory cytokines, thereby reducing mucosal inflammation.
4. Safety and Warnings
Hypersensitivity: Contraindicated in patients with hypersensitivity to mesalazine, salicylates, or excipients (e.g., polysorbates).
Renal and Hepatic: Use with caution in patients with renal or hepatic impairment. Periodic monitoring of renal function (e.g., serum creatinine) is recommended during long-term therapy.
Cardiovascular: Rare cases of myocarditis and pericarditis have been reported; patients should be advised to report chest pain or dyspnea immediately.
5. Adverse Reactions and Clinical Research
Common Adverse Reactions: Headache, abdominal pain, diarrhea, nausea, and flatulence.
Rare/Serious Effects: Acute intolerance syndrome (fever, colic, bloody diarrhea), interstitial nephritis, nephrotic syndrome, pancreatitis, and blood dyscrasias.
6. Drug Interactions
Anticoagulants: May potentiate the effects of oral anticoagulants (e.g., warfarin), increasing the prothrombin time (PT) and bleeding risk.
Azathioprine/6-Mercaptopurine: Concomitant use may increase the risk of bone marrow suppression.
Thiazide Diuretics: May increase the risk of transient increases in blood urea nitrogen (BUN) and serum creatinine.
7. Pharmaceutical Information
Active Ingredient: Mesalazine (5-Aminosalicylic Acid).
Strength: Typically 400 mg per tablet.
Appearance: Pale yellow to yellow, extended-release tablets.
Storage: Store in a tight, light-resistant container at a controlled room temperature (20-25°C), protected from moisture.