Chronic constipation is generally defined as infrequent and difficult passage of stool. One of America's most common disorders, chronic constipation is more often seen in women and in adults aged 65 and older. Symptoms are abdominal pain and discomfort, bloating, straining, and hard stools.
Amitiza works by increasing the secretion of intestinal fluid secretion, which helps ease stool passage and constipation symptoms. The drug should be taken twice daily with food. Doctors and patients should periodically assess the need for continued treatment, states an FDA news release.
The FDA based its decision to approve Amitiza on the results from two clinical trials. When the trial began, participants averaged less than three spontaneous bowel movements per week; they had had constipation symptoms for at least the last six months.
The studies showed that patients treated with Amitiza had more frequent bowel movements in the first week than those taking a fake drug (placebo). In both studies, similar results were seen for the next three weeks of treatment.
In addition, three long-term studies showed that Amitiza decreased constipation severity, abdominal bloating, and discomfort over six to 12 months of use.
The most common adverse events reported in the trials included headache, nausea, diarrhea, abdominal pain, and distension. Whether these events are related to the drug is not yet known.
Amitiza is marketed by Sucampo Pharmaceuticals, Inc., of Bethesda, Md., and by Takeda Pharmaceuticals America of Lincolnshire, Ill.