Brand names Azamune, Berkaprine, Immunoprin, Imuran
Used in the following combinedpreparations None
Azathioprine is an immunosuppressant drug used to prevent immune system rejection of transplanted organs. The drug is also given for severe rheumatoid arthritis that has failed to respond to conventional drug therapy.
Autoimmune and collagen diseases (including polymyositis, systemic lupus erythematosus, myasthenia gravis, chronic inflammatory bowel disease, and dermatomyositis) may also be treated with azathioprine.
Often prescribed when corticosteroids have proved insufficient, azathioprine boosts the effects of these drugs, thus allowing a reduction in the dose of corticosteroids in some cases.
Azathioprine is administered only under close supervision because of the risk of serious adverse effects. These include suppression of the production of white blood cells, thereby increasing the risk of infection as well as the risk of excessive or prolonged bleeding.
Quick Reference
Drug group Antirheumatic drug and immunosuppressant drug
Overdose danger rating Medium
Dependence rating Low
Prescription needed Yes
Available as generic Yes
Information For Users
Your drug prescription is tailored for you.
Do not alter dosage without checking with your doctor.
How taken
Tablets, injection.
Frequency and timing of doses
Usually once daily with or after food.
Dosage range
Initially according to body weight and the condition being treated and then adjusted according to response.
Onset of effect
2-4 weeks. Antirheumatic effect may not be felt for 8 weeks or more.
Duration of action
Immunosuppressant effects may last for several weeks after the drug is stopped.
Storage
Keep in a closed container in a cool, dry place out of the reach of children.
Protect from light.
Missed dose
Take as soon as you remember, then return to your normal schedule. If more than
2 doses are missed, consult your doctor.
Stopping the drug
Do not stop the drug without consulting your doctor. If taken to prevent graft
transplant rejection, stopping treatment could provoke the rejection of the
transplant.
Exceeding the dose
An occasional unintentional extra dose is unlikely to cause problems. Large
overdoses may cause nausea, vomiting, abdominal pains, and diarrhoea. Notify
your doctor.
Possible Adverse Effects
Digestive disturbances and adverse effects on the blood which could lead to sore throat, fever, and weakness are common with azathioprine. Unusual bleeding or bruising while taking this drug may be a sign
of reduced levels of platelets in the blood.
Interactions
Allopurinol
Dosage of azathioprine will need to be reduced if you are taking
allopurinol.
Warfarin
Azathioprine may inhibit the effect of warfarin.
Co-trimoxazole and trimethoprim may increase the risk of blood problems if taken with azathioprine.
Special Precautions
Be sure to tell your doctor if:
You have long-term liver or kidney problems.
You have had an allergic reaction with azathioprine or 6-mercaptopurine.
You have recently had shingles or chickenpox.
You have an infection.
You have unexplained bruising or bleeding, You have a blood disorder.
You are taking other medications.
Pregnancy
Azathioprine has been taken in pregnancy without problems. Discuss with your
doctor.
Breast-feeding
A small amount of the drug passes into the breast milk. Discuss with your doctor.
Infants and children
No special problems.
Over 60
Increased likelihood of adverse effects. Lower doses may be used.
Driving and hazardous work
Avoid such activities until you have learned how azathioprine affects you
because the drug can cause dizziness.
Diet advice
None.
Alcohol
No known problems.
Prolonged Use
There may be a slightly increased risk of some cancers with long-term use of azathioprine. Blood changes may also occur. Avoidance of exposure to sunlight may help to prevent adverse skin effects.
Monitoring Regular checks on blood composition are usually carried out.
