Azathioprine is a drug classified as an immunosuppressant, which means it suppresses the body's immune system. Azathioprine is approved by the U.S. Food and Drug Administration (FDA) for the symptomatic treatment of active rheumatoid arthritis. It is also approved as an adjunctive therapy to prevent kidney transplant rejection.
Azathioprine is used alone or, more commonly, in combination with other drugs (usually corticosteroids) and procedures that affect the immune response.
how it works
Azathioprine works by interfering with the production of DNA and RNA, which are essential for immune cell replication. By inhibiting the proliferation of immune cells, azathioprine helps reduce the body's immune response, thereby preventing rejection of transplanted organs and reducing inflammation in autoimmune diseases.
use
transplant
Azathioprine is often used as part of an immunosuppressive regimen in organ transplant recipients to prevent the body from rejecting the transplanted organ.
Reduce inflammation
Azathioprine is used to treat
- inflammatory bowel disease,
- Churg-Strauss syndrome,
- Autoimmune hepatitis (maintenance treatment with steroids),
- Chronic ITP (second-line drugs),
- lupus nephritis,
- Connective tissue disease-associated ILD,
- multiple sclerosis,
- severe myasthenia gravis,
- recurrent pericarditis,
- psoriasis,
- non-infectious uveitis,
- relapsing polychondritis,
- dermatomyositis/polymyositis,
- Erythema polymorpha,
- Severe and refractory atopic dermatitis,
- chronic actinic dermatitis,
- Pyoderma gangrenosum,
- Behcet's disease,
- Cutaneous vasculitis,
- pityriasis rubra pilaris,
- lichen planus,
- bullous pemphigoid
- Pemphigus vulgaris.
- AZA is a maintenance treatment option for children with Crohn’s disease
side effect
Common side effects
- dose dependent.
- fever
- fatigue
- Arthralgia/myalgia
- rash
- Stomach or intestinal side effects occur in 10-15% of people taking azathioprine, which may include nausea, vomiting, abdominal pain, or diarrhea. Taking azathioprine twice a day instead of all at once, or after meals, may help avoid these problems. Use antiemetics if needed.
- About 5% of people experience side effects such as rash and increased sensitivity to sunlight. It's best to use sunscreen and wear a hat when going out in the sun.
- Effects on Liver and Pancreas: Azathioprine can cause abnormal liver tests or hepatitis. This condition occurs in less than 1% of people taking this medicine. It doesn't cause symptoms unless it's severe, so it's important to get regular blood tests. If you experience symptoms such as yellowing of the whites of your eyes or yellowing of your skin, tell your doctor immediately. Azathioprine can also cause pancreatitis, which can lead to abdominal pain.
- Blood count: Azathioprine can cause a drop in the number of white blood cells, which are needed to fight infection. It may also cause a drop in platelet counts, which can help stop bleeding. Regular blood tests aim to catch these problems early. However, tell your doctor right away if you develop mouth pain, mouth sores, easy bruising, nosebleeds, bleeding gums, difficulty breathing, infection, or fever.
- Hypersensitivity reactions: A small number of people develop hypersensitivity reactions one to two weeks after starting azathioprine. This can cause sudden onset of muscle aches and fever.
- Infections: There is an increased risk of developing certain infections, especially herpes zoster.
Rare side effects
- Cancer: Studies of transplant patients taking azathioprine have found that it may increase the risk of skin cancer. Rheumatic patients who take azathioprine long-term may be at similar risk.
- Depending on the degree and duration of immunosuppression, the risk of other solid organ cancers or blood cancer disorders may also be increased.
- Hair loss includes telogen effluvium, anagen effluvium, and neuropathic folds
- macrocytic anemia
- Pneumonia: IBD and kidney transplant patients
- Upper respiratory tract edema
- Tremor: Transplant and Crohn's Disease Patients: Dose Dependence
What is the dose?
Dosage will be based on your specific immune or inflammatory condition and adjusted based on your weight. Usually start with 50 mg to 100 mg per day. The dose may be increased every 1 to 2 months. The maximum dose is up to 250 mg per day.
Azathioprine can be taken once or twice daily.
Regular monitoring
Patients taking azathioprine need regular monitoring of blood counts, liver function tests, and kidney function to detect any potential side effects early.
Who may not be able to take azathioprine?
- hypersensitivity reaction
- Pregnant or planning pregnancy: Contraception is recommended. AZA increases the risk of spontaneous abortion, low birth weight, and preterm birth. This is despite data from systemic lupus erythematosus (SLE) and kidney transplant patients showing safety during pregnancy. In certain cases, such as systemic lupus erythematosus and antiphospholipid antibody syndrome, taking immunosuppressive drugs may do more good than harm to keep the mother safe.
- Breastfeeding due to the presence of 6-MP in the breast milk of women taking azathioprine
- TPMT status unknown or insufficient TPMT activity due to high risk of myelosuppression
- known malignancy
- clinically active infection
- Have ever had an allergic reaction to azathioprine or any other medicine (including mercaptopurine, a medicine used to treat conditions such as blood cancer)
- any unusual bleeding or bruising
- Have ever had any liver problems
- Have a disease that affects your bone marrow
- due to surgery involving muscle relaxants
- Have Lesch Nyhan syndrome, or a rare genetic disorder that affects your NUDT15 gene
- Ever been told that your body produces too little thiopurine methyltransferase (TMT, an enzyme)
Precautions when using with other drugs
Azathioprine can affect how certain medicines work. Tell your doctor or pharmacist if you:
- taking allopurinol, a drug mainly used to treat gout
- Taking cyclosporine or tacrolimus, immunosuppressant drugs
- Taking warfarin to prevent blood clots
- Are receiving chemotherapy, used to treat cancer
- About to have any type of surgery - tell your doctor or anesthesiologist you are taking azathioprine beforehand
- Have recently received or are about to receive any vaccine, especially a live vaccine such as Zostavax shingles vaccine
- Children taking azathioprine should not receive active childhood influenza vaccine.
Azathioprine brand name
- Azasan
- Azapin
- Imazan
- Imuran
- Thioprine
- Azaprine
in conclusion
Azathioprine is a valuable drug used in the treatment of organ transplantation and autoimmune diseases. While it can effectively suppress the immune system and reduce inflammation, its benefits must be balanced against potential risks and side effects. Patients should be closely monitored by a healthcare professional while taking azathioprine to ensure safe and effective treatment.
