Two medicines, side by side
Azathioprine vs cyclosporine
Azathioprine and cyclosporine are both labeled for rheumatoid arthritis and organ transplant rejection. Drugs@FDA records approvals of azathioprine since 1968 and of cyclosporine since 1983. Pharmacies paid $0.124 per azathioprine 50 mg tablet and $1.04 per unit (Cyclosporine 0.05% eye emulsion) (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. In FDA's classes, azathioprine is a purine antimetabolite and cyclosporine a calcineurin inhibitor immunosuppressant.
Check it at the source: the azathioprine FDA label on DailyMed (effective November 8, 2025); the cyclosporine FDA label on DailyMed (effective August 10, 2026).
Highlights of the azathioprine record
Azathioprine (Imuran) · label of November 8, 2025
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.
Used for
From the label: indicationsIMURAN 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. […]
On the market
- Earliest approval on file
- March 20, 1968
- Generic labelers
- 17 labelers
- Pharmacy cost
- $0.124 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 1
Highlights of the cyclosporine record
Cyclosporine (Restasis) · label of August 10, 2026
Only physicians experienced in management of systemic immunosuppressive therapy for the indicated disease should prescribe Neoral. At doses used in solid organ transplantation, only physicians experienced in immunosuppressive therapy and management of organ transplant recipients should prescribe Neoral. Patients receiving the drug should be managed in facilities equipped and staffed with adequate laboratory and supportive medical resources.
Used for
From the label: indicationsKidney, Liver, and Heart Transplantation Neoral is indicated for the prophylaxis of organ rejection in kidney, liver, and heart allogeneic transplants. Neoral has been used in combination with azathioprine and corticosteroids. Rheumatoid Arthritis Neoral is indicated for the treatment of patients with severe active, rheumatoid arthritis where the disease has not adequately responded to methotrexate. […]
On the market
- Earliest approval on file
- November 14, 1983
- Generic labelers
- 14 labelers
- Pharmacy cost
- $1.04 per unit
Supply and safety
- Shortage
- No current entry
- Recalls
- 7
Source: FDA drug labels via openFDA (Azathioprine label of November 8, 2025, Cyclosporine label of August 10, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do azathioprine and cyclosporine differ on the record?
In FDA's classes, azathioprine is a purine antimetabolite and cyclosporine a calcineurin inhibitor immunosuppressant.
Half-life, in each label's words: Azathioprine, “Maximum serum radioactivity occurs at 1 to 2 hours after oral 35 S-azathioprine and decays with a half-life of 5 hours.”; Cyclosporine, “The disposition of cyclosporine from blood is generally biphasic, with a terminal half-life of approximately 8.4 hours …”
Both labels carry a boxed warning; the records quote them.
Generics: azathioprine since 1995; cyclosporine since 1999 (Drugs@FDA).
| Azathioprine | Cyclosporine | |
|---|---|---|
| Labeled for | Organ transplant rejection, Rheumatoid arthritis | Organ transplant rejection, Rheumatoid arthritis |
| Pharmacologic class | Purine Antimetabolite | Calcineurin Inhibitor Immunosuppressant |
| How it works (label) | n/a | n/a |
| Half-life (label) | Maximum serum radioactivity occurs at 1 to 2 hours after oral 35 S-azathioprine and decays with a half-life of 5 hours. | The disposition of cyclosporine from blood is generally biphasic, with a terminal half-life of approximately 8.4 hours (range, 5 to 18 hours). |
| Earliest approval on file (Drugs@FDA) | March 20, 1968 | November 14, 1983 |
| First generic approved | March 31, 1995 | October 29, 1999 |
| Generic labelers (NDC) | 17 labelers | 14 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.124 per tablet (Azathioprine 50 mg tablet) | $1.04 per unit (Cyclosporine 0.05% eye emulsion) |
| 12-month price change | -10% | -49% |
| Boxed warning | Yes | Yes |
| Shortage now | No current entry | No current entry |
| Recalls recorded | 1 | 7 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 89,586 | 115,545 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What next?
- Alternatives to azathioprine
- every medicine labeled for the same conditions