Purpose: To assess the impact of T in patients with irritable bowel syndrome with constipation (IBS-C) on treatment satisfaction indices. Methods: Women (≤65 years) with IBS-C (Rome II) were randomized to T 6 mg bid or placebo in a double-blind, placebo-controlled multicenter study. Women underwent a 2-week baseline, and two 4-week double-blind Tx periods (P1, then re-randomized to P2), separated by a Tx-free interval. A nine-item questionnaire assessed patients' Tx expectations, satisfaction with Sx relief, and willingness to re-use/recommend Tx at the end of P1 and P2 (analyzed by Cochran-Mantel-Haenszel). Results: 2,660 women with IBS-C were randomized (T [n = 2,135], placebo [n = 525]). Satisfaction data were available for 1,835 T and 434 placebo patients (P1) plus 418/488 T and 418/495 placebo patients (P2). Patients on T had higher Tx satisfaction (p≤0.01) compared with placebo; greater satisfaction with relief of abdominal pain/discomfort, constipation, and other Sx, greater level of expectations being met or exceeded, greater relief of Sx with study medication vs previous medication use, greater future utilization of study medication, and more recommendations of T to others with IBS. Conclusions: This study demonstrated that patients are more satisfied with T as a treatment for IBS-C compared with placebo.Table: No Caption available.