What is the use of Imuran (Azathioprine) medication?

From the Guidelines

Imuran (azathioprine) should be initiated at a dose of 50 mg daily, with gradual increases as needed and tolerated, while monitoring for potential side effects, particularly bone marrow suppression and liver toxicity, as evidenced by studies 1. The medication is commonly used to treat autoimmune conditions like rheumatoid arthritis, lupus, inflammatory bowel disease, and to prevent organ transplant rejection.

• The typical starting dose is 1-2 mg/kg body weight per day, often beginning at 50 mg daily and gradually increasing as needed and tolerated.
• Patients should take Imuran with food to reduce stomach upset.
• Regular blood tests are essential while on this medication to monitor for potential side effects, particularly checking complete blood counts and liver function.
• Common side effects include nausea, vomiting, and increased susceptibility to infections.
• More serious but less common side effects include bone marrow suppression, liver toxicity, and increased risk of certain cancers with long-term use.
• Imuran works by interfering with DNA synthesis in rapidly dividing cells, particularly affecting T and B lymphocytes, thereby reducing immune system activity.
• This medication may take several weeks to months to show full therapeutic effect, so patience is necessary when starting treatment.
• Patients should avoid live vaccines while taking Imuran and inform all healthcare providers about this medication, as recommended by guidelines 1.
• The risk of malignancy with long-term treatment with azathioprine should be considered, and the drug should be continued only when benefits outweigh the risks, as noted in studies 1.

From the FDA Drug Label

Information for Patients: Patients being started on AZASAN should be informed of the necessity of periodic blood counts while they are receiving the drug and should be encouraged to report any unusual bleeding or bruising to their physician. Laboratory Tests: Complete Blood Count (CBC) Monitoring: Patients on AZASAN should have complete blood counts, including platelet counts, weekly during the first month, twice monthly for the second and third months of treatment, then monthly or more frequently if dosage alterations or other therapy changes are necessary The medication Imuran is also known as azathioprine.

• It requires periodic blood counts to monitor for potential side effects.
• Patients should report any unusual bleeding or bruising to their physician.
• CBC monitoring is necessary, with frequency depending on the duration of treatment and any changes to dosage or therapy. 2

From the Research

Imuran Medication Overview

• Imuran, also known as azathioprine, is an immunosuppressive medication used to prevent rejection in organ transplantation and to treat autoimmune diseases 3, 4.
• It belongs to the class of antimetabolites, which inhibit the de novo and salvage pathways of purine synthesis, resulting in lymphocyte suppression 4.

Mechanism of Action and Side Effects

• Azathioprine inhibits the proliferation of T and B lymphocytes, which are involved in the immune response, by interfering with DNA synthesis 4.
• The use of azathioprine can cause several side effects, including bone marrow suppression, leukopenia, thrombocytopenia, and anemia 5, 6, 7.
• Hematologic toxicity is a common adverse effect of azathioprine, and it can be severe in some cases, even in patients without mutations in the thiopurine S-methyltransferase (TPMT) gene 7.

Comparison with Other Immunosuppressants

• Azathioprine has been compared to other immunosuppressants, such as mycophenolate mofetil (MMF), in terms of its effects on the erythropoietic system of renal transplant recipients 6.
• The study found that MMF was associated with higher hemoglobin levels and less bone marrow suppression compared to azathioprine 6.

Clinical Use and Monitoring

• Azathioprine is commonly used in combination with other immunosuppressants, such as cyclosporine and prednisolone, to prevent rejection in organ transplantation 3, 4.
• Patients taking azathioprine require regular monitoring of their blood counts and liver function to minimize the risk of adverse effects 5, 7.