['irritable bowel syndrome characterized by constipation']
['linaclotide', 'placebo']

        Inclusion Criteria:

          -  Patient has no clinically significant findings on a physical examination and clinical
             laboratory tests

          -  Female patients of childbearing potential must agree to use one of the following
             methods of birth control:

               1. Hormonal contraception

               2. Double-barrier birth control

               3. Maintenance of a monogamous relationship with a male partner who has been
                  surgically sterilized by vasectomy

          -  Patient meets protocol criteria for diagnosis of IBS-C

          -  Patient demonstrates continued IBS-C symptoms through Pretreatment Period

          -  Patient maintains a minimum level of compliance with daily diary

        Exclusion Criteria:

          -  Patient has history of loose or watery stools

          -  Patient has symptoms of or been diagnosed with a medical condition that may contribute
             to abdominal pain

          -  Patient has a structural abnormality of the gastrointestinal (GI) tract or a disease
             or condition that can affect GI motility

          -  Patient has any protocol-excluded or clinically significant medical or surgical
             history that could confound the study assessments
      