['constipation - functional']
['lubiprostone']

        Inclusion Criteria:

          -  Has completed the 3-month placebo-controlled study (NCT02042183)

          -  Will continue to abstain from taking concomitant medication (prescribed or
             over-the-counter) that affects gastrointestinal motility

        Exclusion Criteria:

          -  Has untreated faecal impaction at the time of rolling over into study

          -  Has significant change in medical status, newly diagnosed and uncontrolled
             cardiovascular, liver or lung disease, neurologic or psychiatric disorder, or other
             systemic disease

          -  Has demonstrated non-compliance with study protocol during the 3-month
             placebo-controlled study (NCT02042183)
      