Azathioprine

Question 1

Azathioprine indications

Answer 1

Crohns
UC
Autoimmune
Transplant

Question 2

What is azathioprine metabolised to

Answer 2

Mercaptopurine

Question 3

Key interaction of azathioprine

Answer 3

Needs dose reduction when given with allopurinol due to risk of bone marrow suppression

Question 4

Key side effects of Azathioprine

Answer 4

Hypersensitivity reactions (withdraw)
Nausea
Neutropenia
Thrombocytopenia

Question 5

Azathioprine and pregnancy

Answer 5

Premature birth, low birth and spontaneous abortion all possible

Question 6

Monitoring requirements of azathioprine

Answer 6

FBC weekly for 4 weeks then 3 months
Check for toxicity and myelosupression throughout

Question 7

Pre-treatment screening of azathioprine

Answer 7

TPMT metabolises thiopurine drugs. The risk of myelosuppresion is increased in patients reduced activity of this enzyme. TPMT activity should be measured before, if absent activity then cannot use