The use of 6-mercaptopurine in patients with inflammatory bowel disease after failure of azathioprine therapy.
BACKGROUND
Azathioprine is a useful therapy in patients with inflammatory bowel disease that is difficult to control. However, 10% of patients are unable to tolerate azathioprine, and the best form of treatment for this group of patients is unknown. The azathioprine metabolite 6-mercaptopurine may be a useful therapy for these patients.


OBJECTIVE
To review our clinical experience of the use of the 6-mercaptopurine in inflammatory bowel disease patients who are intolerant of azathioprine.


METHODS
All patients who were prescribed 6-mercaptopurine in a 2-year period were identified from pharmacy records. The case notes were reviewed and those who had previously been intolerant of azathioprine were included.


RESULTS
A total of 19 with either ulcerative colitis and Crohn's disease were included. The reasons for discontinuing azathioprine were side-effects (13 patients), failure of efficacy (four patients) and leucopenia (two patients). Eleven of the 19 patients (68%) tolerated 6-mercaptopurine, including seven out of 13 patients (54%) who discontinued azathioprine due to side-effects. The length of follow-up of patients on 6-mercaptopurine was between 126 and 780 days (median 390 days).


CONCLUSIONS
6-mercaptopurine should be considered in patients with inflammatory bowel disease who require continuing immunosuppressive therapy, but are intolerant of azathioprine.
Boulton-Jones
J R
JR
Kingsmill Hospital, Mansfield Road, Sutton-in-Ashfield, UK. robandal@1leesroad.freeserve.co.uk
Pritchard
K
K
Mahmoud
A A
AA
D000328:Adult; D000368:Aged; D001379:Azathioprine / Q000627:therapeutic use*; D003093:Colitis, Ulcerative / Q000188:drug therapy*; D003424:Crohn Disease / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D008297:Male; D015122:Mercaptopurine / Q000009:adverse effects / Q000627:therapeutic use*; D008875:Middle Aged
D007166:Immunosuppressive Agents; D015122:Mercaptopurine; D001379:Azathioprine