After 30 minutes of rest following tube placement, fasting colonic tone, colonic compliance and colonic sensation were tested. The last dose of medication was ingested and 1 hour later the same colonic functions, as well as colonic response to a standardized meal of a 1,000-kilocalorie chocolate milkshake were assessed. The participant was able to leave the study center in the afternoon, after a meal had been ingested (if desired).