Azathioprine Sodium
Azathioprine Sodium is an immunosuppressive medication that works by inhibiting the synthesis of DNA and RNA in rapidly dividing cells, thereby suppressing immune system activity. It is primarily used to prevent organ rejection in transplant patients and to treat various autoimmune conditions such as rheumatoid arthritis, lupus, and inflammatory bowel disease.
Azathioprine Sodium is an immunosuppressant used to prevent transplant rejection and treat autoimmune disorders by suppressing cell division and immune function.
Key facts at a glance
- RxNorm
- 267476
- Generic
- Azathioprine Sodium
- Class
- pin-variant
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- —
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
7 groupspregnancy
first trimesteravoid if possible
avoid use during pregnancy unless benefits outweigh risks; consider discontinuation before planned pregnancy
regular fetal monitoring
Use of this medication in this population requires careful consideration of risks and benefits.
pregnancy
second third trimestermaintain lowest effective dose
continue only if benefits outweigh risks; close monitoring of maternal and fetal status
regular fetal growth monitoring, ultrasound assessments
Use with caution and monitor for adverse effects.
lactation
breastfeedingno specific adjustment
considered compatible with breastfeeding per AAP; monitor infant for unusual symptoms
observe infant for signs of infection or bone marrow suppression
Use with caution and monitor for adverse effects.
pediatric_age
children 2 17 yearsweight-based dosing starting at 1-2 mg/kg/day
use with caution; monitor CBC regularly; adjust dose based on response and tolerability
complete blood count weekly initially, then monthly
Use with caution and monitor for adverse effects.
geriatric
elderly over 65start at lower end of dosing range, 1-1.5 mg/kg/day
use with caution due to increased susceptibility to infections and myelosuppression
frequent CBC monitoring, renal and hepatic function assessment
Use with caution and monitor for adverse effects.
renal_impairment
moderate severereduce dose by 25-50% in moderate impairment; 50-75% reduction in severe impairment
use with caution; metabolites accumulate in renal impairment
monitor CBC, renal function, adjust dose based on hematologic response
Use with caution and monitor for adverse effects.
hepatic_impairment
moderate severereduce dose by 25-50% in moderate impairment; avoid in severe impairment if possible
use with caution; drug is metabolized in liver
monitor CBC, liver function tests, adjust dose based on response
Use with caution and monitor for adverse effects.
Statistics and clinical data
FDA approval year
Initial FDA approval for azathioprine
Drug class
WHO ATC code L04AX01
Common uses
Primary therapeutic applications
Mechanism of action
Molecular mechanism of immunosuppression
Prevention of organ transplant rejection (kidney, liver, heart); treatment of rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease (Crohn's disease, ulcerative colitis), and certain hematologic conditions such as immune thrombocytopenia and autoimmune hemolytic anemia.
Azathioprine is a prodrug that is converted to 6-mercaptopurine (6-MP) in the body. It inhibits purine synthesis, which disrupts DNA and RNA production. This prevents rapid proliferation of immune cells (particularly T-cells and B-cells), thereby suppressing the immune response that would otherwise attack transplanted organs or cause autoimmune inflammation.
Requires regular blood monitoring to check blood counts due to risk of bone marrow suppression. Increases susceptibility to infections and certain cancers. Should not be used during pregnancy unless clearly needed. May interact with allopurinol (requires dose reduction) and other immunosuppressants. Patients should avoid live vaccines while taking this medication.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 24, 2026. · Read our editorial policy