The ten-year single-center experience with 6-mercaptopurine in the treatment of inflammatory bowel disease.
OBJECTIVE
To report the 10-year experience of a single center in treating patients with refractory inflammatory bowel disease (IBD) with relatively lower dose of 6-mercaptopurine (6-MP).


METHODS
The charts of 285 patients with IBD (Crohn's disease 160 and ulcerative colitis 125) receiving 6-MP were reviewed. Clinical response, subsequent breakthrough while taking 6-MP, and relapse rates when 6-MP was discontinued and side effects were assessed.


RESULTS
Ninety-three percent of the patients were taking 50 to 75 mg/day of 6-MP. Complete remission was achieved in 62%, partial remission in 14.5%, and failure to achieve remission in 23.5% of the patients. Of complete responders, 27.5% had breakthrough while continuing 6-MP. Nine percent of those that achieved a complete remission experienced a relapse after 6-MP was discontinued. Side effects included leukopenia (11.2%), abnormal liver function tests (3.8%), various infections, including pneumonia (3.1%), pancreatitis (2.5%), nausea (2.1%), headache (2.8%), fever (1.4%), hair loss (1%), and rash (0.7%). Two cancers occurred while taking 6-MP: melanoma on the finger and a fatal colonic lymphoma. Four patients continued 6-MP throughout pregnancies and had normal outcomes.


CONCLUSIONS
In our experience 6-MP is relatively safe and appears to be as effective at a lower dosage (0.84 mg/kg per day) compared with the recommended higher dosage (1-1.5 mg/kg per day), when leukopenia was more frequent. Serious side effects, although rare, need to be monitored.
Glazier
Kenneth D
KD
Crohn's and Colitis Center of NJ, Division of Gastroenterology and Hepatology, Department of Medicine, UMDNJ-Robert Wood Johnson Medical School, New Brunswick, NJ 0893, USA.
Palance
Adam L
AL
Griffel
Louis H
LH
Das
Kiron M
KM
D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D015212:Inflammatory Bowel Diseases / Q000188:drug therapy*; D008297:Male; D015122:Mercaptopurine / Q000009:adverse effects / Q000627:therapeutic use*; D012008:Recurrence; D013997:Time Factors
D007166:Immunosuppressive Agents; D015122:Mercaptopurine