Azathioprine: uses, dosing, side effects & brands
Azathioprine is a medicine sold in the U.S. under one brand. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Available as
- Tablet
- Sold as
- Imuran
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
- What the pharmacy pays
- about $4 for a 30-count supply — not your price
Every azathioprine product we track (1)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
Only one: Imuran.
How long azathioprine keeps
The date on a sealed pack is not the only one: some azathioprine labels start a second clock once the product is opened or mixed, as short as 24 hours.
Does azathioprine expire? The in-use limits and storage rules from its labelsAzathioprine and breastfeeding
From LactMed, the US National Library of Medicine’s Drugs and Lactation Database — quoted, not rewritten.
Full LactMed record for azathioprine: levels in milk, effects in breastfed infants, and the drugs it would consider insteadStudies in women with inflammatory bowel disease, systemic lupus erythematosus or transplantation taking doses of azathioprine up to 200 mg daily for immunosuppression have found either low or unmeasurable levels of the active metabolites in milk and infant serum. Some evidence indicates a lack of adverse effects on the health and development of infants exposed to azathioprine during breastfeeding up to 4.6 years of age, but long-term follow-up for effects such as carcinogenesis have not been performed. Azathioprine has been extensively used by nursing mothers and numerous experts and professional guidelines have stated that the drug is a low risk to the nursing infant and acceptable to use during breastfeeding.
National Institute of Child Health and Human Development, record revised November 15, 2025. LactMed states its information is not a substitute for professional judgement.
What people report to the FDA about azathioprine
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 2,534 reports naming azathioprine, and the FDA flagged 99% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- arthralgia545 reports
- fatigue540 reports
- drug intolerance461 reports
- headache456 reports
- hepatic enzyme increased449 reports
- alopecia431 reports
- nausea414 reports
- intentional product use issue410 reports
Read these as a signal, not a rate. A report does not mean azathioprine caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 25, 2026.
Related calculators
Frequently asked questions
Can you take azathioprine with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run azathioprine against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What forms does azathioprine come in?
Across the brands we track, azathioprine is currently marketed as tablet, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic azathioprine?
We do not currently list a generic-labelled azathioprine product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Azathioprine: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/azathioprine
- MLA
- “Azathioprine: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/azathioprine.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for azathioprine on DailyMed (NIH) ↗.