Azathioprine 50mg

 Immunosuppressant

“ALERT: US Boxed Warning

Malignancy:

Chronic immunosuppression with azathioprine, a purine antimetabolite, increases risk of malignancy in humans. Reports of malignancy include post-transplant lymphoma and hepatosplenic T-cell lymphoma in patients with inflammatory bowel disease. Health care providers using this drug should be very familiar with this risk, as well as with the mutagenic potential to both men and women, and with possible hematologic toxicities. Inform patients of the risk of malignancy with azathioprine.”

CSA NA – FDA Approved – REMS (N) – Can Ship

Azathioprine, Imuran/Azasan is a derivative of mercaptopurine in the body and its metabolites inhibit purine synthesis.  Purines are the building blocks of DNA and RNA and when the metabolites are incorporated into the replicating strands DNA and RNA, cell division halts.  These same metabolites also mediate most of the immunosuppressive and toxic effects of Azathioprine, Imuran/Azasan.

Officially indicated for prevention of organ rejection after kidney transplantation and to treat active rheumatoid arthritis.  It is also prescribed off-label for Crohn disease, dermatomyositis/polymyositis, eosinophilic granulomatosis with polyangiitis, erythema multiforme, heart transplant, hepatitis, immune thrombocytopenia, liver transplant, lupus nephritis, myasthenia gravis, pemphigus vulgaris, pericarditis, psoriasis, ulcerative colitis, and uveitis.

Risk of GI hypersensitivity symptoms which can include severe nausea, vomiting, diarrhea, rash, fever, malaise, myalgia, hypotension and elevated LFTs

Risk of hematologic toxicity, hepatotoxicity, infections, malignancy

Use with caution in patients with hepatic and renal impairment

Azathioprine, Imuran/Azasan Usual Dosing

Kidney transplantation – prevention of rejection

Oral: 2mg to 3mg/kg (usual dose: 50mg to 150mg daily)

Rheumatoid arthritis

Oral: 25mg to 50mg daily; dose can be increased by 50mg/day every 4 weeks.  The maximum daily dose is 3mg/kg if required.

How to Take Azathioprine, Imuran/Azasan:  Most commonly taken once daily after a meal; can be taken in divided doses to reduce gastric upset.

Make Sure to Adhere to Close Monitoring: Extensive lab monitoring is required including but not limited to CBC/diff, platelets, LFTs, bilirubin and CrCl.

The frequency of side effects is not defined, dependent upon the dose, duration, and concomitant therapy.

Central Nervous System: Malaise

Gastrointestinal: Nausea and vomiting (rheumatoid arthritis: 12%), diarrhea

Hematologic & Oncologic: Leukopenia (renal transplant: >50%; rheumatoid arthritis: 28%), neoplasia (renal transplant 3% [other than lymphoma], 0.5% [lymphoma]), thrombocytopenia

Hepatic: Hepatotoxicity, increased serum alkaline phosphatase, increased serum bilirubin, increased serum transaminases

Infection: Increased susceptibility to infection (renal transplant 20%; rheumatoid arthritis <1%; includes bacterial, fungal, protozoal, viral, opportunistic, and reactivation of latent infections)