Lubiprostone, a locally acting highly selective type-2 chloride channel activator, has been US FDA approved since January 2006 for the treatment of adults with chronic idiopathic constipation and FDA approved since April 2008 for the treatment of woman aged 18 years or older suffering from irritable bowel syndrome (IBS) with constipation. Through activation of the type-2 chloride channels located on the luminal side of intestinal epithelial cells, it promotes fluid secretion, increasing the liquid content of stool and accelerating small bowel as well as colonic transit. Lubiprostone has demonstrated efficacy with respect to increasing weekly spontaneous bowel movements and improving stool consistency, straining and constipation severity, both in short- and long-term studies. It has also demonstrated efficacy in the treatment of IBS with constipation, with beneficial effects on global symptoms, abdominal pain, constipation-related symptoms and overall quality of life. There is no evidence of a rebound in constipation or IBS symptoms following cessation of lubiprostone. In general, lubiprostone is well tolerated, with the most common side effects including nausea, headache and diarrhea.