Zelnorm Overview:
Zelnorm (tegaserod) is a medication that was designed to treat constipation predominant IBS (IBS-C) and chronic idiopathic constipation (CIC). Due to concerns about serious health risks, the medication is currently restricted to prescription only on an emergency basis with direct authorization from the Food and Drug Administration (FDA).
The Zelnorm Problem:
Although many people experienced significant symptom relief from Zelnorm, some clinical trials indicated a small but significant risk of cardiovascular difficulties, including heart attack, stroke, and unstable angina. This risk was identified in March of 2007, resulting in Zelnorm being taken off the market. However, in response to patient demand, in July of 2007 Zelnorm was once again made available, but only to patients who met very specific criteria regarding their health history. As of April 2008, this restricted access program was discontinued, resulting in the current status of emergency use only.
Limits on Zelnorm Prescriptions:
Zelnorm can only be prescribed on an emergency basis. The FDA defines an emergency as a condition that is “immediately life threatening or serious enough to qualify for hospitalization.” In such cases, direct authorization is required from the FDA and the FDA may deny such authorization if there is any evidence of risk factors, such as cardiovascular disease, anxiety and depression, obesity, smoking and diabetes.
How Zelnorm Works:
Zelnorm is thought to work by acting on the 5-HT4 receptors for the neurotransmitter serotonin (5-HT) in the cells of the gut’s own nervous system. This is thought to stimulate gut motility, resulting in an increase in intestinal movement and a decrease in transit time, as well as to increase the secretion of liquids resulting in a softer, easier to pass stool.
Zelnorm's Efficacy:
Research has shown that Zelnorm is effective in increasing the frequency of spontaneous bowel movements that feel complete to the patient. Use of Zelnorm also appears to result in a decrease in straining and an increase in patient satisfaction regarding bowel habits.
Zelnorm Side Effects:
Research indicated that in most cases, Zelnorm was well-tolerated. In clinical trials, some patients experienced mild and transient diarrhea, but less than one percent of these patients discontinued the medication as a result. It was the reports of serious cardiovascular problems in a sub-group of patients that resulted in the current restrictions.
The Future of Zelnorm:
One study followed a large group of Zelnorm users for approximately two and a half years and did not find an increased risk for cardiovascular problems. However, it seems unlikely that research such as this will be enough to change the FDA's policy. The problem remains that a side effect as serious as death must be weighed against any positive treatment results. In the meantime, constipation patients must look to to find symptom relief.
Sources:
American College of Gastroenterology Chronic Constipation Task Force "An Evidence-Based Approach to the Management of Chronic Constipation in North America" The American Journal of Gastroenterology 2005 100:S1-S4.
Anderson JL, May HT, Bair TL, Muhlestein JB, Horne BD, & Carlquist JF "Lack of Association of Tegaserod With Adverse Cardiovascular Outcomes in a Matched Case-Control Study." Journal of Cardiovascular Pharmacological Therapy 2009.
Gaman, A., Bucur, M. & Kuo, B. Therapeutic advances in functional gastrointestinal disease: irritable bowel syndrome Therapeutic Advances in Gastroenterology 2009 2:169-181.
Sources, cont.:
Zelnorm (tegaserod maleate) Information. US Food and Drug Administration. Accessed November 13, 2009.
