Prescription medicine
Azathioprine Brand names: Imuran, Azasan
Azathioprine (Imuran) is a prescription medicine with an FDA approval on record since 1968. FDA's NDC Directory lists it from 17 generic labelers, and pharmacies paid $0.124 per azathioprine 50 mg tablet in the October 7, 2026 NADAC survey.
- Generic listed
- Boxed warning
Check it at the source: the azathioprine FDA label on DailyMed (effective November 8, 2025, Sebela Pharmaceuticals Inc.); the NDA 16324 record on Drugs@FDA; every azathioprine label on DailyMed.
Highlights of the record
FDA label of November 8, 2025; NDC Directory, Drugs@FDA and Orange Book, October 8, 2026; NADAC October 7, 2026
MALIGNANCY Chronic immunosuppression with IMURAN, a purine antimetabolite increases risk of malignancy in humans. Reports of malignancy include post-transplant lymphoma and hepatosplenic T-cell lymphoma (HSTCL) in patients with inflammatory bowel disease. Physicians 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. Physicians should inform patients of the risk of malignancy with IMURAN. See WARNINGS.
Used for
From the label: indications and usageIMURAN is indicated as an adjunct for the prevention of rejection in renal homotransplantation.
Forms and strengths
- 25 mg
- 50 mg
- 75 mg
- 100 mg
- 100 mg/10ml
Tablet; injection (powder) (lyophilized) for solution.
On the market
- Earliest approval on file
- March 20, 1968 Imuran, Legacy; Drugs@FDA’s file, where older or withdrawn approvals can be missing
- Generic approvals
- 6 first March 31, 1995; 6 with a marketed status in Drugs@FDA
- Labelers listed (NDC)
- 19 of which 17 under generic applications, 2 under brand applications, repackagers included
Supply and safety
- Pharmacy cost (NADAC)
- $0.124 per tablet Azathioprine 50 mg tablet
- Shortage (FDA)
- No current entry
- Recalls by its makers (FDA)
- 1 since 2013 0 Class I among all firms' recalls; latest April 4, 2014; 1 more by firms not listed as its makers
- FAERS reports
- 89,586 through July 30, 2026
What is azathioprine used for?
From the label: indications and usageIMURAN is indicated as an adjunct for the prevention of rejection in renal homotransplantation. It is also indicated for the management of active rheumatoid arthritis to reduce signs and symptoms. Renal Homotransplantation: IMURAN is indicated as an adjunct for the prevention of rejection in renal homotransplantation. Experience with over 16,000 transplants shows a 5-year patient survival of 35% to 55%, but this is dependent on donor, match for HLA antigens, anti-donor or anti-B-cell alloantigen antibody, and other variables. The effect of IMURAN on these variables has not been tested in controlled trials. […]
Conditions named in the indications of azathioprine's FDA labels, with every medicine labeled for each:
FDA pharmacologic class: Purine Antimetabolite.
Source: FDA drug label (IMURAN), NDA016324 (Legacy), as published by Sebela Pharmaceuticals Inc., effective November 8, 2025 (SPL set 606101a0-6244-7eff-e053-2a91aa0acadd), via openFDA; the full label on DailyMed
Is there a generic for azathioprine (Imuran)?
The FDA approved the first generic azathioprine on March 31, 1995. 6 generic applications are approved; 6 of them carry a current (not discontinued) marketing status in Drugs@FDA; that status is not evidence that the generic is on sale.
FDA's NDC Directory lists azathioprine from 17 labelers under a generic (ANDA) application and from 2 brand labelers. A listing means the company has registered the product for sale; it does not show that every pharmacy stocks it.
- 1968 earliest approval on file
- 1995 first generic approved
- red ticks recalls
Source: Drugs@FDA, FDA NDC Directory and the Orange Book (openFDA bulk files, October 8, 2026)
What do pharmacies pay for azathioprine (Imuran)?
In CMS's NADAC survey of October 7, 2026, pharmacies paid $0.124 per Azathioprine 50 mg tablet, down 10% from $0.138 on October 8, 2025. Prices per unit in the table differ many-fold by strength, form and brand, so compare like with like. The chart's scale runs from the lowest to the highest price shown, not from zero. NADAC is what retail pharmacies paid their wholesalers, per unit, in CMS's monthly survey; what a patient pays depends on insurance and the pharmacy.
- Azathioprine 50 mg tablet (generic)
| Strength and form | Brand or generic | Pharmacy cost | 30 tablets, or one pen or vial | 12-month change |
|---|---|---|---|---|
| Azathioprine 100 mg tablet | Generic | $3.31 per tablet many times the lowest per-tablet cost; NADAC records the price, not why | $99.44 | -31% |
| Azathioprine 50 mg tablet | Generic | $0.124 per tablet | $3.73 | -10% |
| Azathioprine 75 mg tablet | Generic | $7.66 per tablet many times the lowest per-tablet cost; NADAC records the price, not why | $229.70 | -27% |
Source: CMS National Average Drug Acquisition Cost (NADAC) survey, October 7, 2026: what retail pharmacies paid per unit; not a counter price
Has azathioprine been recalled?
The FDA's Enforcement Report lists 2 recalls naming azathioprine since 2013: 0 Class I (the most serious), 1 Class II, 1 Class III; 0 still ongoing. 1 of them is by a firm that FDA's NDC Directory does not list as a maker of azathioprine and that holds no application for it in Drugs@FDA, such as compounding pharmacies or bulk-ingredient suppliers; the recall notice names the product recalled. A recall names products and lots, not every product of the medicine.
| Started | Class | Company | Reason |
|---|---|---|---|
| April 4, 2014 | Class III | Boehringer Ingelheim Roxane Inc | Labeling: Incorrect or Missing Lot and/or Exp Date: This recall is being conducted because the product was given 36 month expiration dates instead of the filed … |
| July 2, 2013 | Class II | Aidapak Services, LLC not a listed maker | Labeling: Label Mixup: azaTHIOprine, Tablet, 50 mg may have potentially been mislabeled as the following drug: SELENIUM, Tablet, 50 mcg, NDC 00904316260 … |
Source: FDA Enforcement Report (drug recalls) via openFDA, through October 8, 2026
What does the azathioprine label say about other medicines?
The azathioprine label names 9 other medicines in its interaction, contraindication or warning sections. The labels of 27 other medicines name azathioprine. The sentences are the labels' own; a label lists what its studies and reports found, not every interaction.
| Medicine named | Section | What the label says |
|---|---|---|
| Allopurinol | drug interactions | Drug Interactions: Use with xanthine oxidase (XO) inhibitors: One of the pathways for inactivation of azathioprine is inhibited by XO inhibitors (allopurinol or febuxostat). |
| Chlorambucil | contraindications | Patients with rheumatoid arthritis previously treated with alkylating agents (cyclophosphamide, chlorambucil, melphalan, or others) may have a prohibitive risk of malignancy if treated with IMURAN. |
| Cyclophosphamide | contraindications | Patients with rheumatoid arthritis previously treated with alkylating agents (cyclophosphamide, chlorambucil, melphalan, or others) may have a prohibitive risk of malignancy if treated with IMURAN. |
| Febuxostat | drug interactions | Drug Interactions: Use with xanthine oxidase (XO) inhibitors: One of the pathways for inactivation of azathioprine is inhibited by XO inhibitors (allopurinol or febuxostat). |
| Melphalan | contraindications | Patients with rheumatoid arthritis previously treated with alkylating agents (cyclophosphamide, chlorambucil, melphalan, or others) may have a prohibitive risk of malignancy if treated with IMURAN. |
| Olsalazine | drug interactions | Use with Aminosalicylates: There is in vitro evidence that aminosalicylate derivatives (e.g., sulphasalazine, mesalazine, or olsalazine) inhibit the TPMT enzyme. |
| Prednisone | warnings | In a detailed case report, 4 documented lymphopenia, diminished IgG and IgM levels, CMV infection, and a decreased thymic shadow were noted in an infant born to a mother receiving 150 mg azathioprine and 30 mg prednisone daily throughout pregnancy. |
| Ribavirin | drug interactions | 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. |
| Warfarin | drug interactions | Use with Warfarin: IMURAN may inhibit the anticoagulant effect of warfarin. |
Other labels that name azathioprine
Source: FDA drug label (IMURAN), NDA016324 (Legacy), as published by Sebela Pharmaceuticals Inc., effective November 8, 2025 (SPL set 606101a0-6244-7eff-e053-2a91aa0acadd), via openFDA; the full label on DailyMed
What do FAERS reports show for azathioprine?
The FDA Adverse Event Reporting System holds 89,586 reports that list azathioprine among the medicines taken, through July 30, 2026, each a report of something that happened, not proof the medicine caused it; 9,288 are coded as a death and 31,035 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is.
Reports received each year
The most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026
What else is labeled for the same conditions as azathioprine?
5 other medicines are given the same way (oral) and in the same FDA class as azathioprine or labeled mainly for the same use (organ transplant rejection), the same class first. Organ transplant rejection lists all 13 medicines labeled for it, by any route. They are listed as records, not as substitutes: whether one can replace another is a prescriber's decision.
| Medicine | Shared indication | Generic labelers (oral) | Pharmacy cost | Shortage |
|---|---|---|---|---|
| Tacrolimus | Organ transplant rejection | 30 labelers | $0.123 per capsule 0.5 mg capsule (immediate release) | No current entry |
| Mycophenolate mofetil | Organ transplant rejection | 30 labelers | $0.138 per capsule 250 mg capsule | No current entry |
| Mycophenolic acid | Organ transplant rejection | 16 labelers | $0.0996 per tablet 180 mg tablet | No current entry |
| Sirolimus | Organ transplant rejection | 18 labelers | $0.723 per tablet 1 mg tablet | No current entry |
| Cyclosporine | Rheumatoid arthritis, Organ transplant rejection | 8 labelers | $0.314 per unit 25 mg | No current entry |
Every medicine labeled for the same conditions as azathioprine
Source: FDA drug labels (indications), NDC Directory, NADAC of October 7, 2026, FDA shortages (October 8, 2026)
How does azathioprine compare with medicines for the same use?
6 side-by-side pages set azathioprine beside a medicine whose label shares a use: approvals, generics, pharmacy cost, warnings and supply.
What next?
- Alternatives to azathioprine
- 5 medicines for the same use
- Other purine antimetabolites
- the pharmacologic class, with prices and generics
- Azathioprine side effects
- the label's list beside FAERS reports
- Check an interaction
- what two or more labels say about each other