Jr. Boulton-jones et al., The use of 6-mercaptopurine in patients with inflammatory bowel disease after failure of azathioprine therapy, ALIM PHARM, 14(12), 2000, pp. 1561-1565
Introduction: Azathioprine is a useful therapy in patients with inflammator
y bowel disease that is difficult to control. However, 10% of patients are
unable to tolerate azathioprine, and the best form of treatment for this gr
oup of patients is unknown. The azathioprine metabolite 6-mercaptopurine ma
y be a useful therapy for these patients.
Aim: To review our clinical experience of the use of the 6-mercaptopurine i
n inflammatory bowel disease patients who are intolerant of azathioprine.
Methods: All patients who were prescribed 6-mercaptopurine in a 2-year peri
od 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 w
ere included. The reasons for discontinuing azathioprine were side-effects
(13 patients), failure of efficacy (four patients) and leucopenia (two pati
ents). Eleven of the 19 patients (68%) tolerated 6-mercaptopurine, includin
g seven out of 13 patients (54%) who discontinued azathioprine due to side-
effects. The length of follow-up of patients on 6-mercaptopurine was betwee
n 126 and 780 days (median 390 days).
Discussion: 6-mercaptopurine should be considered in patients with inflamma
tory bowel disease who require continuing immunosuppressive therapy, but ar
e intolerant of azathioprine.