Azathioprine
Azathioprine is an immune-suppressing medicine used to help prevent rejection of a transplanted kidney and to treat active rheumatoid arthritis.
Built from the FDA-approved label, dated Nov 8, 2025 · How this page is built
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert ▾
Long-term use of azathioprine increases the risk of cancer. This includes lymphoma after a transplant. A rare, aggressive and often fatal lymphoma called hepatosplenic T-cell lymphoma has been reported in people with inflammatory bowel disease.
The medicine can also harm blood cell counts and has mutagenic potential (the ability to cause genetic changes) in both men and women. Your doctor should discuss these risks with you. Report any new lumps, skin changes, unexplained fevers or other unusual symptoms promptly.
⚡ Quick answers about Azathioprine
What is azathioprine used for?
It helps prevent your body from rejecting a transplanted kidney, and it is also used to reduce the signs and symptoms of active rheumatoid arthritis. It works by calming down the immune system.
See it in the FAQ →How do I take it?
The tablets (Imuran, Azasan or generic azathioprine) are taken by mouth, usually once daily, though for rheumatoid arthritis the day's dose may be split in two. Follow your prescriber's directions exactly.
Read the full answer →How long before it works for my arthritis?
It usually takes about 6 to 8 weeks, and your doctor will want to give it at least 12 weeks before deciding whether it is helping. Keep taking it as directed in the meantime.
See it in the FAQ →Why do I need so many blood tests?
Azathioprine can lower your white blood cells, platelets and red blood cells, sometimes severely.
Read the full answer →🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 20 clinical label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
How we combine label and product data →📖 Azathioprine: Patient Information Guide
A plain-language walkthrough of Azathioprine — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.
What Azathioprine is used for
▾
Azathioprine is used for two main conditions.
- Preventing rejection after a kidney transplant (renal homotransplantation), as an add-on to other treatment. This applies to Azathioprine Sodium for Injection (intravenous) and to Imuran, Azasan and generic azathioprine tablets.
- Reducing the signs and symptoms of active rheumatoid arthritis, for the same injection and tablet products.
How Azathioprine works
▾
Azathioprine is a purine antimetabolite, a type of medicine that suppresses the immune system. Your body breaks it down extensively, and one of its products is mercaptopurine. Usual doses produce low blood levels of both azathioprine and mercaptopurine.
How Azathioprine is taken (dosage)
▾
Azathioprine tablets are taken by mouth, generally once daily. For rheumatoid arthritis the daily amount may be split into two doses. Azathioprine Sodium for Injection is given into a vein, and it is used only in people who cannot tolerate oral medicines.
- Your dose depends on your condition, weight and blood test results.
- For rheumatoid arthritis, benefit usually takes 6 to 8 weeks, and an adequate trial is at least 12 weeks.
- For rheumatoid arthritis, the label says it can be stopped abruptly, but delayed effects are possible. Check with your prescriber before stopping.
Dosing details from the FDA-approved label
From the Azathioprine prescribing information (“Dosage and Administration”). Doses are set by your prescriber for your product, condition, kidney function and age — never change a dose on your own.
- Renal Homotransplantation
- The initial dose is usually 3 to 5 mg/kg daily, beginning at the time of transplant
- Usually given as a single daily dose on the day of, and in a minority of cases 1 to 3 days before, transplantation
- Dose reduction to maintenance levels of 1 to 3 mg/kg daily is usually possible
- The dose should not be increased to toxic levels because of threatened rejection. IV sodium salt is indicated only in patients unable to tolerate oral medications; tablets are then used at the same dose level after the postoperative period.
- Rheumatoid Arthritis
- Usually given daily
- The initial dose should be approximately 1 mg/kg (50 to 100 mg) given as a single dose or on a twice-daily schedule
- The dose may be increased, beginning at 6 to 8 weeks and thereafter by steps at 4-week intervals, if there are no serious toxicities and if initial response is unsatisfactory, in increments of 0.5 mg/kg daily
- Maintenance
- Maximum: 2.5 mg/kg/day
- An adequate trial is a minimum of 12 weeks; patients not improved after 12 weeks can be considered refractory.
- Patients with homozygous deficiency in either TPMT or NUDT15
- Consider alternative therapies for patients known to have TPMT or NUDT15 deficiency because of the risk of increased toxicity
- Patients with heterozygous deficiency in TPMT and/or NUDT15
- Dosage reduction is recommended in patients known to have heterozygous deficiency of TPMT or NUDT15
- Patients heterozygous for both TPMT and NUDT15 deficiency may require more substantial dosage reductions.
- Use in Renal Dysfunction
- Relatively oliguric patients, especially those with tubular necrosis in the immediate postcadaveric transplant period, are usually given lower doses
- They may have delayed clearance of azathioprine or its metabolites and may be particularly sensitive to the drug.
- Parenteral Administration
- Add 10 mL of Sterile Water for Injection and swirl until clear
- This solution, equivalent to 100 mg azathioprine, is for intravenous use only and should be used within 24 hours
- Further dilution into sterile saline or dextrose is usually made for infusion, usually over 30 to 60 minutes, but as short as 5 minutes and as long as 8 hours for the daily dose
Read the label’s full dosing text
DOSAGE AND ADMINISTRATION: TPMT TESTING CANNOT SUBSTITUTE FOR COMPLETE BLOOD COUNT (CBC) MONITORING IN PATIENTS RECEIVING IMURAN. TPMT genotyping or phenotyping can be used to identify patients with absent or reduced TPMT activity. Patients with low or absent TPMT activity are at an increased risk of developing severe, life-threatening myelotoxicity from IMURAN if conventional doses are given. Physicians may consider alternative therapies for patients who have low or absent TPMT activity (homozygous for non-functional alleles). IMURAN should be administered with caution to patients having one non-functional allele (heterozygous) who are at risk for reduced TPMT activity that may lead to toxicity if conventional doses are given. Dosage reduction is recommended in patients with reduced TPMT activity. Early drug discontinuation may be considered in patients with abnormal CBC results that do not respond to dose reduction. Renal Homotransplantation: The dose of IMURAN required to prevent rejection and minimize toxicity will vary with individual patients; this necessitates careful management. The initial dose is usually 3 to 5 mg/kg daily, beginning at the time of transplant. IMURAN is usually given as a single daily dose on the day of, and in a minority of cases 1 to 3 days before, transplantation. Dose reduction to maintenance levels of 1 to 3 mg/kg daily is usually possible. The dose of IMURAN should not be increased to toxic levels because of threatened rejection. Discontinuation may be necessary for severe hematologic or other toxicity, even if rejection of the homograft may be a consequence of drug withdrawal. Rheumatoid Arthritis: IMURAN is usually given on a daily basis. The initial dose should be approximately 1.0 mg/kg (50 to 100 mg) given as a single dose or on a twice-daily schedule. The dose may be increased, beginning at 6 to 8 weeks and thereafter by steps at 4-week intervals, if there are no serious toxicities and if initial response is unsatisfactory. Dose increments should be 0.5 mg/kg daily, up to a maximum dose of 2.5 mg/kg per day. Therapeutic response occurs after several weeks of treatment, usually 6 to 8; an adequate trial should be a minimum of 12 weeks. Patients not improved after 12 weeks can be considered refractory.
Excerpted — the section continues on the label. Read the full Dosage and Administration section on DailyMed →
Azathioprine side effects in detail
▾
Common side effects
- Low white blood cell count (leukopenia)
- Stomach and bowel problems (gastrointestinal effects)
- Low blood counts, including platelets and red blood cells
- Infections
When to get medical help
- Call your doctor about signs of infection, such as fever or chills, because azathioprine can lead to serious or even fatal infections.
- Get medical help for unusual bleeding or bruising, severe tiredness or paleness. These can signal low blood counts or bone marrow suppression.
- Tell your doctor right away about new neurological symptoms. Azathioprine and similar medicines have been linked to a rare brain infection called PML.
- Report any new skin changes or lumps, since the risk of skin cancer and lymphoma is higher.
- If you are pregnant and develop symptoms of intrahepatic cholestasis of pregnancy (a liver condition of pregnancy), contact your doctor. The medicine should be stopped if it develops.
The main side effects involve your blood and digestive system.
- Low white blood cell count (leukopenia)
- Other low blood counts, including platelets and anemia
- Stomach and bowel (gastrointestinal) problems
- Infections
Contact your doctor promptly for fever or signs of infection, unusual bleeding or bruising, or new neurological symptoms.
Azathioprine warnings and precautions
▾
- Cancer risk: Immune suppression raises the risk of lymphoma and other cancers, especially skin cancer. Protect your skin from sun and ultraviolet light.
- Low blood counts: Severe drops in white cells, platelets and red cells, and bone marrow suppression, can occur. Regular blood counts are needed.
- TPMT or NUDT15 deficiency: This raises the risk of severe, life-threatening bone marrow toxicity, and deaths have been reported in people with absent TPMT activity.
- Serious infections: These include bacterial, viral, fungal and opportunistic infections, and some can be fatal.
- PML: A rare, sometimes fatal brain infection has been reported with immunosuppressants.
- Pregnancy: Azathioprine can cause fetal harm.
Azathioprine interactions: what it interacts with
▾
Several medicines can change how azathioprine works or raise its toxicity.
- Allopurinol: azathioprine dose is cut to about one-third to one-quarter.
- Febuxostat: not recommended, as it can raise azathioprine levels and cause toxicity.
- Aminosalicylates: they may inhibit the TPMT enzyme, so use with caution.
- Co-trimoxazole and similar drugs: may cause exaggerated low white cell counts.
- ACE inhibitors: have been linked to anemia and severe leukopenia.
- Warfarin: its blood-thinning effect may be reduced.
- Ribavirin: can cause severe pancytopenia, so blood counts need close monitoring.
Interactions listed in the FDA-approved label
From the Azathioprine prescribing information (“Drug Interactions”): what the manufacturer studied or reported to the FDA.
- Xanthine oxidase (XO) inhibitors (allopurinol or febuxostat): Inhibition of XO may cause increased plasma concentrations of azathioprine or its metabolite 6-MP, leading to toxicity. With allopurinol, reduce the azathioprine dose to approximately 1/3 to 1/4 the usual dose. Concomitant use with febuxostat is not recommended. Consider further dose reduction or alternative therapies in patients with low or absent TPMT activity.
- Aminosalicylates (sulphasalazine, mesalazine, olsalazine): There is in vitro evidence that aminosalicylate derivatives inhibit the TPMT enzyme. Concomitant use should be done with caution.
- Other agents affecting myelopoesis (including co-trimoxazole): Drugs which may affect leukocyte production may lead to exaggerated leukopenia, especially in renal transplant recipients.
- Angiotensin-converting enzyme inhibitors: Use of ACE inhibitors to control hypertension in patients on azathioprine has been reported to induce anemia and severe leukopenia.
- Warfarin: Azathioprine may inhibit the anticoagulant effect of warfarin.
- Ribavirin: Ribavirin for hepatitis C in patients receiving azathioprine has been reported to induce severe pancytopenia and may increase the risk of azathioprine-related myelotoxicity. Monitor complete blood counts, including platelet counts, weekly for the first month, twice monthly for the second and third months, then monthly or more frequently if dosage or other therapy changes are necessary.
Read the label’s full interactions text
Drug Interactions Use with xanthine oxidase (XO) inhibitors : One of the pathways for inactivation of azathioprine is inhibited by XO inhibitors (allopurinol or febuxostat). Patients receiving azathioprine and allopurinol concomitantly should have a dose reduction of azathioprine, to approximately 1/ 3 to 1/ 4 the usual dose. Concomitant use of azathioprine with febuxostat is not recommended. Inhibition of XO may cause increased plasma concentrations of azathioprine or its metabolite, 6-MP, leading to toxicity. It is recommended that a further dose reduction or alternative therapies be considered for patients with low or absent TPMT activity receiving azathioprine and xanthine oxidase inhibitors because both TPMT and XO inactivation pathways are affected (see CLINICAL PHARMACOLOGY , WARNINGS , PRECAUTIONS: Laboratory Tests and ADVERSE REACTIONS sections). Use with Aminosalicylates There is in vitro evidence that aminosalicylate derivatives (e.g., sulphasalazine, mesalazine, or olsalazine) inhibit the TPMT enzyme. Concomitant use of these agents with azathioprine tablets should be done with caution. Use with Other Agents Affecting Myelopoesis Drugs which may affect leukocyte production, including co-trimoxazole, may lead to exaggerated leukopenia, especially in renal transplant recipients. Use with Angiotensin-Converting Enzyme Inhibitors The use of angiotensin-converting enzyme inhibitors to control hypertension in patients on azathioprine has been reported to induce anemia and severe leukopenia. Use with Warfarin Azathioprine tablets may inhibit the anticoagulant effect of warfarin. Use with ribavirin The use of ribavirin for hepatitis C in patients receiving azathioprine has been reported to induce severe pancytopenia and may increase the risk of azathioprine-related myelotoxicity. Inosine monophosphate dehydrogenase (IMDH) is required for one of the metabolic pathways of azathioprine.
Excerpted — the section continues on the label. Read the full Drug Interactions section on DailyMed →
Not a complete list. The label covers the interactions the manufacturer studied or reported, and our own interaction database does not cover every medicine either. Bring your full medication list, including vitamins and herbal products, to your pharmacist.
Before taking Azathioprine
▾
- Do not use if you are allergic to azathioprine.
- Do not use for rheumatoid arthritis during pregnancy.
- If you have rheumatoid arthritis and previously took alkylating agents such as cyclophosphamide, chlorambucil or melphalan, the cancer risk may be prohibitive.
- Tell your prescriber if you could become pregnant or are pregnant. Women of childbearing age should avoid becoming pregnant.
- Discuss TPMT or NUDT15 testing if you have had severe bone marrow problems.
- Do not use with other disease-modifying anti-rheumatic drugs (DMARDs) for rheumatoid arthritis unless your prescriber directs it. The label says this combination has not been studied and cannot be recommended.
Azathioprine overdose: if you take too much
▾
Very large doses can cause bone marrow suppression, bleeding, infection and death. In one reported case of a very large single dose, the person had nausea, vomiting and diarrhea, followed by mild leukopenia and mild liver test abnormalities. These returned to normal within about 6 days. Seek emergency help if you take too much.
Pharmacokinetics: how your body processes Azathioprine
▾
Azathioprine is well absorbed after oral use. Peak levels of its breakdown products appear about 1 to 2 hours after a dose and decline with a half-life of about 5 hours. That figure reflects all the breakdown products together rather than azathioprine itself. The body metabolizes the drug extensively, so only a fraction remains as azathioprine.
How to store Azathioprine
▾
Store at 20-25 °C (USP Controlled Room Temperature) (68° to 77°F) in a dry place and protect from light.
📄 Written from Azathioprine’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →
Supplements & herbs that interact with Azathioprine
106 supplements and herbal products have documented interactions with Azathioprine in the licensed clinical database we use. Most are manageable — but your pharmacist should know about everything you take, including vitamins and herbals.
- Major · 4
- Moderate · 92
- Minor · 10
Educational information from a licensed clinical database (Natural Medicines) — see our data sources & update cadence. Not medical advice: an interaction being documented does not mean it will happen to you; do not start or stop medications or supplements without professional guidance.
Nutrient depletion considerations
Azathioprine has been associated with lower levels of 1 nutrient in the clinical literature. This does not mean a deficiency will occur — it means these may be worth discussing with your pharmacist or healthcare provider, especially with long-term use.
Educational information from a licensed clinical database (Natural Medicines) — not medical advice. Do not start or stop medications or supplements without professional guidance.
🩺 Azathioprine: pharmacist answers to common questions
Quick, plain-English answers to the questions patients ask most about Azathioprine — the kind of thing our pharmacy team would talk through with you at the counter.
What is azathioprine used for?
▾
How do I take it?
▾
How long before it works for my arthritis?
▾
Why do I need so many blood tests?
▾
What should I avoid or tell my doctor about?
▾
Is it safe during pregnancy?
▾
Is Azathioprine available over the counter?
▾
When was Azathioprine first available?
▾
Who makes Azathioprine?
▾
💬 Answers drafted from Azathioprine’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →
🧰 More about Azathioprine on HelloPharmacist
💊 Azathioprine forms and strengths (how it comes)
Azathioprine is available in 2 forms. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Tablet
How this form is used
- Imuran is used as an add-on to help prevent rejection after a kidney transplant and for active rheumatoid arthritis.
- Azasan is used as an add-on to help prevent rejection after a kidney transplant and for active rheumatoid arthritis.
- Azathioprine tablets are used as an add-on to help prevent rejection after a kidney transplant and for active rheumatoid arthritis.
- Imuran, Azasan and azathioprine tablets are usually taken once daily for kidney transplant.
- Imuran, Azasan and azathioprine tablets are usually taken daily for rheumatoid arthritis, as one dose or two.
- Imuran, Azasan and azathioprine tablets need regular blood count monitoring, and your prescriber may consider TPMT testing.
Injection
How this form is used
- Azathioprine Sodium for Injection is used as an add-on to help prevent rejection after a kidney transplant.
- Azathioprine Sodium for Injection is also used for active rheumatoid arthritis.
- Azathioprine Sodium is given into a vein and is indicated only for people who cannot tolerate oral medicines.
- Azathioprine Sodium is often started at the time of transplant, with tablets used afterward at the same dose level once the postoperative period has passed.
📊 Azathioprine on the U.S. market: products, makers and brands
How Azathioprine appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
32 companies list 94 Azathioprine product records with the FDA, mostly as tablet, injection; the earliest marketing or approval year on record is 1968. Brand names on the directory include Azasan, Imuran; the rest are generics.
FDA-listed product records by dose form (tablet variants merged) — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
Also listed with the FDA, not a patient dose form: Powder (12) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.
Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
📈 How widely Azathioprine is used (Medicaid data)
A general measure of how commonly Azathioprine is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Azathioprine is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Azathioprine prescribed? Of the 1,600 medications we measure, Azathioprine ranks #484 by Medicaid prescriptions — more than 70% of them.
Utilization by Azathioprine product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
azathioprine 50 MG Oral Tablet Most dispensed
Summed across the 6 of 29 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 197388
azathioprine 100 MG Oral Tablet
Summed across the 3 of 13 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 359228
azathioprine 75 MG Oral Tablet
Summed across the 3 of 12 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 359229
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Azathioprine, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 12 of 54 listed Azathioprine NDCs with Medicaid activity.
🔍 Compare Azathioprine products
A representative set of FDA-listed product records for Azathioprine — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Injection | ||||
| 100 mg/10 mL | Intravenous | Hikma Pharmaceuticals USA Inc. × 2 listings | ANDA | View NDC → |
| 100 mg/10 mL | Intravenous | West-Ward Pharmaceuticals Corp | ANDA | View NDC → |
| 💊Tablet | ||||
| 50 mg | Oral | American Health Packaging × 3 listings | ANDA | View NDC → |
| 50 mg | Oral | Amneal Pharmaceuticals NY LLC × 5 listings | ANDA | View NDC → |
| 75 mg | Oral | Amneal Pharmaceuticals NY LLC × 4 listings | ANDA | View NDC → |
| 100 mg | Oral | Amneal Pharmaceuticals NY LLC × 4 listings | ANDA | View NDC → |
| 50 mg | Oral | Aphena Pharma Solutions - Tennessee, LLC × 2 listings | ANDA | View NDC → |
| 25 mg | Oral | Ascend Laboratories, LLC × 2 listings | ANDA | View NDC → |
| 50 mg | Oral | Ascend Laboratories, LLC × 2 listings | ANDA | View NDC → |
| 75 mg | Oral | Ascend Laboratories, LLC × 2 listings | ANDA | View NDC → |
| 100 mg | Oral | Ascend Laboratories, LLC × 2 listings | ANDA | View NDC → |
| 50 mg | Oral | AvKARE × 3 listings | ANDA | View NDC → |
| 100 mg | Oral | AvKARE × 2 listings | ANDA | View NDC → |
| 50 mg | Oral | Glenmark Pharmaceuticals, Inc × 4 listings | ANDA | View NDC → |
| 50 mg | Oral | Golden State Medical Supply, Inc. × 2 listings | ANDA | View NDC → |
| 50 mg | Oral | Golden State Medical Supply Inc. | ANDA | View NDC → |
| 50 mg | Oral | Legacy Pharma USA Inc. | NDA | View NDC → |
| 50 mg | Oral | NuCare Pharmaceuticals, Inc. | ANDA | View NDC → |
| 50 mg | Oral | NuCare Pharmaceuticals,Inc. | ANDA | View NDC → |
| 75 mg | Oral | Oceanside Pharmaceuticals × 2 listings | ANDA | View NDC → |
| 100 mg | Oral | Oceanside Pharmaceuticals × 2 listings | ANDA | View NDC → |
| 50 mg | Oral | PD-Rx Pharmaceuticals, Inc. × 3 listings | ANDA | View NDC → |
| 50 mg | Oral | Remedyrepack Inc. × 2 listings | ANDA | View NDC → |
| 50 mg | Oral | Rising Pharma Holdings, Inc. | ANDA | View NDC → |
| 75 mg | Oral | Salix Pharmaceuticals × 3 listings | ANDA | View NDC → |
| 100 mg | Oral | Salix Pharmaceuticals × 3 listings | ANDA | View NDC → |
| 50 mg | Oral | Sebela Pharmaceuticals Inc. × 2 listings | NDA | View NDC → |
| 25 mg | Oral | Zydus Lifesciences Limited × 2 listings | ANDA | View NDC → |
| 50 mg | Oral | Zydus Lifesciences Limited × 2 listings | ANDA | View NDC → |
| 75 mg | Oral | Zydus Lifesciences Limited × 2 listings | ANDA | View NDC → |
| 100 mg | Oral | Zydus Lifesciences Limited × 2 listings | ANDA | View NDC → |
| 25 mg | Oral | Zydus Pharmaceuticals USA Inc. × 3 listings | ANDA | View NDC → |
| 50 mg | Oral | Zydus Pharmaceuticals USA Inc. × 3 listings | ANDA | View NDC → |
| 75 mg | Oral | Zydus Pharmaceuticals USA Inc. × 3 listings | ANDA | View NDC → |
| 100 mg | Oral | Zydus Pharmaceuticals USA Inc. × 3 listings | ANDA | View NDC → |
| 💊Bulk drug substance | ||||
| 1 kg/kg | — | Aarti Pharmalabs Limited | BULK INGREDIENT | View NDC → |
| 1 kg/kg | — | APICHEM Laboratories Private Limited | BULK INGREDIENT | View NDC → |
| 1 kg/kg | — | Apicore Pharmaceuticals Private Limited | BULK INGREDIENT | View NDC → |
| 1 kg/kg | — | Fermion Oy | BULK INGREDIENT | View NDC → |
| 1 kg/kg | — | Fine Chemicals Corporation (PTY) Ltd. | BULK INGREDIENT | View NDC → |
| 1 g/g | — | Letco Medical, Llc | BULK INGREDIENT FOR HUMAN PRESCRIPTION COMPOUNDING | View NDC → |
| 1 g/g | — | Medisca Inc. | BULK INGREDIENT | View NDC → |
| 1 kg/kg | — | Professional Compounding Centers of America dba PCCA | BULK INGREDIENT FOR HUMAN PRESCRIPTION COMPOUNDING | View NDC → |
| 1 kg/kg | — | Rakshit Drugs Private Limited | BULK INGREDIENT | View NDC → |
| 1 kg/kg | — | Spectrum Laboratory Products, Inc. | BULK INGREDIENT | View NDC → |
| 1 kg/kg | — | Zhejiang Cheng Yi Pharmaceutical Co., Ltd | BULK INGREDIENT | View NDC → |
| 1 kg/kg | — | Zydus Lifesciences Limited | BULK INGREDIENT | View NDC → |
Showing 94 of 94 products — FDA National Drug Code Directory. See every product, package size and price: browse all 94 Azathioprine NDCs →
📈 Azathioprine side effects reported to the FDA (FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Azathioprine — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Azathioprine in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
🏛️ Azathioprine FDA approval history
How Azathioprine went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
🚨 Azathioprine recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
Source: openFDA drug enforcement (recall) reports.
RxNorm Concept Web — From Ingredient to Every Form and Strength
This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.
RxCUI 1256 2 dose forms · 6 strengths
-
Dose form (SCDF) Injection RxCUI 1789839In current FDA listingsClinical drug / strength (SCD) 100 MGRxCUI 239983 -
Dose form (SCDF) Oral Tablet RxCUI 370973In current FDA listings
Look up RxCUI 1256 in the RxCUI Atlas →
RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.
📦 Azathioprine supply and shortage status
Whether Azathioprine is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
🏷️ Azathioprine brand names
Azathioprine is sold under 2 brand names in the FDA directory — Azasan, Imuran. A brand and its generic contain the same active ingredient; the brand name belongs to one company's product.
🏭 Who makes Azathioprine: manufacturers and labelers
32 companies list Azathioprine products with the FDA. By number of product records, the largest are Amneal Pharmaceuticals NY LLC, Zydus Pharmaceuticals USA Inc., Zydus Lifesciences Limited. Labelers include manufacturers and repackagers; the product in your bottle depends on which one your pharmacy stocks.
…and 8 more on the FDA NDC directory.
Azathioprine drug class (RxNorm)
Azathioprine belongs to the Purine Antimetabolite class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
🔬 Sources for this Azathioprine page
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How we combine label and product data
HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 20 FDA-filed SPL label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.
For canonical ingredient pages, bounded product-attributed indication and administration excerpts may be added to the AI evidence, and the generator is instructed to preserve available product, brand, route, and form qualifiers instead of treating one label as universal. Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Sebela Pharmaceuticals Inc. is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.
This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.