Mercaptopurine Mesalamine

Lowry PW, Franklin CL, Weaver AL, Szumlanski CL, Mays DC, Loftus EV, Tremaine WJ, Lipsky JJ, Weinshilboum RM, Sandborn WJ. Leucopenia resulting from a drug interaction between azathioprine or 6-mercaptopurine and mesalamine, sulphasalazine, or bal-salazide. Gut 2001 49(5) 656-64. 

Azathioprine and mercaptopurine are effective for long-term treatment of Crohn s disease and ulcerative colitis." These agents are generally reserved for patients who are refractory to steroids, and they may be associated with serious adverse effects such as lymphomas, pancreatitis, or nephrotoxicity. They are usually used in conjunction with mesalamine derivatives and/or steroids, and must be used for long periods of time (from a few weeks up to 6 months) before benefits may be observed." Remission can be prolonged by azathioprine in steroid-dependent patients with ulcerative colitis." Cyclosporine... 

Drug intolerance often limits the usefulness of agents used to treat IBD. Many patients receiving sulfasalazine, mesalamine, corticosteroids, metronidazole, azathioprine, mercaptopurine, or infliximab experience some undesired effects. In some cases, these adverse effects can be significant and require discontinuation of the therapy. Knowledge of the common or important adverse reactions will assist in avoiding or minimizing their effects. 

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