Diarrhea Predominant Irritable Bowel Syndrome in Females

Clinical Trial with TRN-002 in Women with Irritable Bowel Syndrome (IBS) The purpose of this study is to investigate the safety and effectiveness of a new investigational drug in women for the treatment of diarrhea-predominant irritable bowel syndrome. The investigational drug is a natural product taken from a plant that grows in South America. The study medication will be administered orally twice a day. Subjects will be not able to remain on certain standard IBS medications (anti-diarrheals) while participating in the study. The total duration of the study is 18 weeks. The study requires five study visits that include physical exams, ECG, blood draws, laboratory studies, and a colon procedure (such as a colonoscopy or flexible sigmoidoscopy if an appropriate procedure has not been performed in the last 5 years.) Participants will be asked to make entries into a touch-tone telephone diary on a daily basis. Participants must meet all of the following criteria: * Females at least 18 years of age * Diagnosis of diarrhea predominant Irritable Bowel Syndrome * Willingness to make daily calls on a touch-tone telephone * Willingness to have an endoscopic and/or radiologic bowel evaluation, if you have not received one in the past 5 years. * Willingness to take an approved method of birth control (if required) Participants CANNOT meet any of the following criteria: * Serious medical or surgical conditions * Colon Cancer, Crohns Disease or Ulcerative Colitis * Pregnant or breast feeding