Azathioprine

Please note: these are basic guidelines, refer to your doctor for a professional medical opinion.

Popular brand names:

Azamun, Azapress, Imuran, Zaprine

Drug group:

Antirheumatic and immunosuppressant drug

Prescription needed?

Yes

What does it do?

Azathioprine is used:

• To prevent immune-system rejection of transplanted organs
• In the treatment of severe rheumatoid arthritis – when conventional drug therapy has failed, to modify or slow the underlying disease process
• In combination with corticosteroids in the treatment of autoimmune and collagen diseases - polymyositis, systemic lupus erythematosus, myasthenia gravis, dermatomyositis

How should it be used?

• Azathioprine is always administered under close supervision
• Tablets should be taken with or after food
• Avoid exposure to sunlight to avoid adverse skin effects

What is the typical dosage?

Your doctor will recommend a dosage tailored to your need, but typically:

• Starting dose is calculated according to body weight and the condition being treated
• Dose is then adjusted according to response

How quickly will it start to work?

2–4 weeks (8 or more weeks in rheumatoid arthritis)
  

How long will the effects last?

Immunosuppressant effects may last for several weeks after the drug is stopped.
                    

When should I stop using it?

Do not stop the drug without consulting your doctor.

Is it safe for prolonged use?

Long term use may suppress bone marrow activity, leading to less production of all types of blood cells. This increases the risk of infections (reduced white cells) and excessive or prolonged bleeding (reduced platelets). There may be a genetic susceptibility to this. There is also a small increase in the risk of cancers affecting the immune system.

Regular checks on blood chemistry and blood cell counts are needed.

What are the possible side effects?

The following have been reported:

• More common: nausea, vomiting, loss of appetite, hair loss, weakness
• Less common: unusual bleeding or bruising
• Report to your doctor before taking your next dose if you experience: jaundice, rash, fever, chills

What other considerations are important?

Dosage may be adjusted by your doctor under certain conditions.

• Certain health problems: liver/kidney problems, previous allergic reaction to azathioprine or 6-mercaptopurine, recent shingles/chickenpox, current infections, blood disorder
• Other medicines: Allopurinol, warfarin, co-trimoxazole, trimethoprim, mesalazine, olsalazine, sulfasalazine, corticosteroids
• Pregnancy and breast-feeding: No problems expected but discuss with your doctor
• Children: No special problems
• Over 60: Reduced dose necessary, increased risk of side effects
• Driving and hazardous work: Caution, the drug can cause dizziness
• Alcohol: No known problems