Azathioprine
Prescription ·Exploratory record · not publication-reviewed ·Updated July 13, 2026
Azathioprine is a thiopurine immunosuppressant used for kidney transplant rejection prophylaxis and autoimmune diseases such as rheumatoid arthritis, inflammatory bowel disease, and others when clinically appropriate. It can cause life-threatening myelosuppression, infection, hepatotoxicity, pancreatitis, and malignancy risk, with TPMT and NUDT15 genetics and xanthine oxidase inhibitor interactions strongly affecting safety.
Exploratory record, not a reviewed medical publication.
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This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.
What the research says.
A quick, data-only summary. The full evidence, dosing, and sources are below.
Azathioprine is a thiopurine immunosuppressant used for kidney transplant rejection prophylaxis and autoimmune diseases such as rheumatoid arthritis, inflammatory bowel disease, and others when clinically appropriate. NutriStack rates the supporting evidence as strong. Common adult dosing is Transplant: often 3 to 5 mg/kg daily initially, then maintenance commonly 1 to 3 mg/kg daily. Autoimmune indications commonly start around 1 mg/kg daily and titrate cautiously by response, blood counts, liver tests, and TPMT/NUDT15 risk., though a prescriber sets the actual dose. This profile indexes 3 sources.
- Prevention of kidney transplant rejection as part of immunosuppressive regimens3
- Steroid-sparing maintenance therapy in selected autoimmune diseases
- Treatment of rheumatoid arthritis when other therapies are unsuitable
- Maintenance therapy in selected inflammatory bowel disease patients
The bottom line
Evidence rating strong. Most-documented uses: prevention of kidney transplant rejection as part of immunosuppressive regimens, steroid-sparing maintenance therapy in selected autoimmune diseases, treatment of rheumatoid arthritis when other therapies are unsuitable. 3 sources indexed (2011–2026), with 0 interaction records on file.
How it works, mechanistically.
Core mechanism
Azathioprine is converted to 6-mercaptopurine and then to active thioguanine nucleotides that interfere with de novo purine synthesis and lymphocyte proliferation. Because activated T and B lymphocytes depend heavily on purine synthesis, immune responses are suppressed. TPMT and NUDT15 activity influence active metabolite accumulation and myelotoxicity risk.2,3
Dosing & protocol.
May be taken with food to reduce nausea. Consistent administration and close blood count monitoring are more important than meal timing.1
Full safety detail.
Side effects
- Leukopenia
- Thrombocytopenia
- Anemia
- Serious infections
- Nausea and vomiting
- Hepatotoxicity
- Pancreatitis
- Hypersensitivity fever or rash
- Lymphoma and other malignancies
- Nonmelanoma skin cancer risk
Contraindications
- Known hypersensitivity to azathioprine or mercaptopurine2,3
- Avoid use for rheumatoid arthritis in pregnancy unless benefits clearly outweigh risks
- Use extreme caution or dose reduction with low or absent TPMT or NUDT15 activity1
- Major interaction with allopurinol or febuxostat requires avoidance or substantial dose reduction3
- Live vaccines are generally avoided during significant immunosuppression3
Sources, by evidence tier.
Numbered references. Citations throughout the page link here.
Reviews & position papers
2- 1Clinical Pharmacogenetics Implementation Consortium guideline for thiopurine dosing based on TPMT and NUDT15 genotypesRelling MV et al. · Clinical Pharmacology and Therapeutics · 2019
Guideline supports dose reduction or alternative therapy in patients with reduced TPMT or NUDT15 function.
- 2Use of azathioprine in clinical medicineMaltzman JS et al. · Clinical Pharmacology and Therapeutics · 2011
Review covers mechanism, clinical uses, metabolism, and adverse-effect monitoring.
Reference material
1- 3Imuran Azathioprine Tablets US Prescribing InformationURLU.S. National Library of Medicine · DailyMed · 2026
Labeling describes malignancy boxed warning, transplant and RA dosing, myelosuppression, infection, hepatotoxicity, and xanthine oxidase inhibitor interactions.
Common questions.
Quick answers about Azathioprine, drawn from the data on this page.
What is Azathioprine?
Azathioprine is a thiopurine immunosuppressant used for kidney transplant rejection prophylaxis and autoimmune diseases such as rheumatoid arthritis, inflammatory bowel disease, and others when clinically appropriate. It can cause life-threatening myelosuppression, infection, hepatotoxicity, pancreatitis, and malignancy risk, with TPMT and NUDT15 genetics and xanthine oxidase inhibitor interactions strongly affecting safety.
What is Azathioprine used for?
Commonly cited benefits of Azathioprine include: Prevention of kidney transplant rejection as part of immunosuppressive regimens; Steroid-sparing maintenance therapy in selected autoimmune diseases; Treatment of rheumatoid arthritis when other therapies are unsuitable; Maintenance therapy in selected inflammatory bowel disease patients. NutriStack rates the overall evidence as strong.
What is a typical dose of Azathioprine?
A typical adult dose of Azathioprine is Transplant: often 3 to 5 mg/kg daily initially, then maintenance commonly 1 to 3 mg/kg daily. Autoimmune indications commonly start around 1 mg/kg daily and titrate cautiously by response, blood counts, liver tests, and TPMT/NUDT15 risk.. The commonly recommended form is Oral tablet; injectable formulation in supervised settings when oral therapy is not possible. These are general ranges, not personalized advice; confirm the right dose with a clinician.
What are the side effects of Azathioprine?
Reported side effects include leukopenia, thrombocytopenia, anemia, serious infections, nausea and vomiting, hepatotoxicity. This is educational information; check with a healthcare professional before use.
How strong is the evidence for Azathioprine?
NutriStack rates this as Strong, meaning multiple high-quality meta-analyses or systematic reviews converge on the same finding. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.
Use this with your stack
Azathioprine in NutriStack.
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