A person should seek medical care if the diarrhea lasts for more than 2 weeks or is accompanied with symptoms such as weight loss, fatigue, and abdominal pain. The treatment of microscopic colitis has not been standardized because there have not been adequate large scale, prospective, placebo controlled treatment trials. The following strategies are safe and may relieve diarrhea in some patients: Avoid nonsteroidal antiinflammatory drugs (NSAIDs) Trial of lactose elimination (just to eliminate the possibility that intolerance to lactose in milk is aggravating the diarrhea) Antidiarrhea agents such as loperamide (Imodium) or diphenoxylate and atropine (Lomotil) Bismuth subsalicylate such as Pepto-Bismol budesonide (Entocort EC) 5-ASA (mesalamine) compounds such as Asacol, Pentasa, or Colazal Controlled trials showed that budesonide (Entocort, a poorly absorbed steroid) is effective in controlling diarrhea in more than 75% of the patients with collagenous colitis, but the diarrhea tends to recur soon after stopping Entocort. Though data supporting their use is lacking, some doctors may use medications that potently suppress the immune system such as azathioprine (Imuran, Azasan) and 6-mercaptopurine in patients with severe microscopic colitis that is unresponsive to other treatments.