Mezavant (Mesalazine)

• Mezavant, a 5‑ASA drug, is used in the management of inflammatory bowel disease, specifically ulcerative colitis.
• Ulcerative colitis (induction): reduces disease activity and promotes mucosal healing to achieve remission.
• Ulcerative colitis (maintenance): helps sustain remission and prevent relapse by providing continuous anti‑inflammatory effect.
• Mild to moderate ulcerative colitis: alleviates symptoms such as abdominal pain, diarrhea, and rectal bleeding through localized action.

• Mesalazine exerts its anti‑inflammatory effect by inhibiting the cyclooxygenase (COX) and lipoxygenase (LOX) pathways within colonic epithelial cells. This blockade reduces the synthesis of prostaglandins and leukotrienes, key mediators of inflammation, thereby decreasing mucosal edema, leukocyte infiltration, and ulceration in the colon. The drug is released primarily in the distal ileum and colon, allowing high local concentrations while systemic exposure remains low, which contributes to its favorable safety profile.

Mesalazine may cause a range of adverse reactions, which are categorized by frequency and severity.

Common Side Effects

• Nausea
• Abdominal pain
• Headache
• Flatulence
• Rash

Serious or Rare Side Effects

• Myocarditis
• Pancreatitis
• Severe allergic reaction (e.g., Stevens‑Johnson syndrome)
• Blood dyscrasias such as neutropenia or agranulocytosis
• Elevated liver enzymes or hepatitis

• Before initiating Mezavant, clinicians should consider several precautionary measures to ensure safe use.
• Renal function: assess baseline renal function and monitor periodically, as mesalazine can affect kidney performance.
• Hepatic function: evaluate liver enzymes before treatment and during therapy, especially in patients with pre‑existing liver disease.
• Disease activity: confirm active ulcerative colitis and avoid use during severe flare without appropriate monitoring.
• Hypersensitivity: do not prescribe to patients with known allergy to mesalazine or other salicylates.
• Concomitant NSAIDs: use with caution, as combined therapy may increase risk of renal impairment.
• Store at ambient temperature: keep tablets in the original container, protect from moisture and light.

Mesalazine can interact with other medicines, and some combinations require avoidance while others need careful monitoring.

Major Interactions (Avoid)

• Azathioprine: increased risk of bone marrow suppression.
• Warfarin: enhanced anticoagulant effect leading to bleeding.
• Methotrexate: heightened toxicity and hepatic injury.

Moderate Interactions (Monitor Closely)

• Oral contraceptives: reduced hormonal efficacy, consider alternative contraception.
• Lithium: possible alteration of lithium serum levels.
• Allopurinol: may increase the incidence of skin reactions.