Zymurine Tablet contains Azathioprine 50mg, an immunosuppressive agent primarily used to prevent organ transplant rejection and to manage autoimmune disorders such as rheumatoid arthritis, Crohn’s disease, and ulcerative colitis. Azathioprine acts by inhibiting purine synthesis, thereby suppressing the proliferation of immune cells, particularly T and B lymphocytes, which are responsible for the pathological immune response. This mechanism reduces inflammation and immune-mediated tissue damage. Zymurine is indicated for patients requiring long-term immunosuppression and should be administered under strict medical supervision due to potential adverse effects. Common side effects include gastrointestinal disturbances, such as nausea and vomiting, as well as hematologic abnormalities like leukopenia, thrombocytopenia, and anemia, necessitating regular blood count monitoring. Hepatotoxicity and increased susceptibility to infections are also notable risks. Dosage adjustments may be required based on clinical response and laboratory parameters. Contraindications include hypersensitivity to Azathioprine or its metabolites and active infections. Caution is advised in patients with impaired hepatic or renal function. Zymurine should not be used during pregnancy unless the potential benefits outweigh the risks. Patient counseling should emphasize adherence to prescribed doses and immediate reporting of adverse symptoms.