Mesalamine Tablets

Mechanism

Mesalamine inhibits cyclooxygenase and lipoxygenase pathways, reducing prostaglandin and leukotriene synthesis. It acts topically in the intestinal mucosa to suppress inflammation and promote mucosal healing.

Pharmacokinetics

• Absorption: Variable; depends on formulation (delayed-release or extended-release). Peak plasma concentration in 4–12 hours.
• Distribution: Plasma protein binding ~43%; concentrated in intestinal mucosa.
• Metabolism: Acetylated in intestinal mucosa and liver to inactive N-acetyl mesalamine.
• Excretion: Primarily via urine as N-acetyl mesalamine; some unchanged drug in feces.
• Half-life: ~5–10 hours depending on formulation.
• Special Populations: Clearance reduced in renal impairment; caution required. Minimal systemic absorption reduces systemic side effects.

Side Effects

• Abdominal pain
• Nausea
• Headache
• Diarrhea
• Rare: nephrotoxicity, pancreatitis

Contraindication

• Hypersensitivity to salicylates or mesalamine
• Severe renal impairment
• Severe hepatic impairment

Interaction

• Azathioprine/6-mercaptopurine (increased risk of myelosuppression)
• NSAIDs (additive renal toxicity)
• Warfarin (altered anticoagulant effect)

Warning and Precautions

• Monitor renal function during therapy
• Use under medical supervision only
• Caution in patients with liver disease

Dosage

As directed by the Physician.