After patients complete the above treatment and tests, they undergo a second colonoscopy within 48 hours of their last dose of study medication and may be offered another 1-week supply of medication. Those for whom additional treatment is deemed potentially beneficial are offered another 4-week course of drug or placebo (continuing whichever they took the first 4 weeks). They come to the clinic for two visits 2 weeks apart (days 43 and 57) for a physical examination, blood tests, EKG, pregnancy test for women, CDAI, IBDQ and review of medications and symptoms. A urine sample is collected only on day 57. A third colonoscopy is done after all the tests are completed on day 57, within 48 hours after the last dose of study medication.