Reviewed by: HU Medical Review Board | Last reviewed: March 2023 | Last updated: April 2023
Zelnorm (tegaserod) is a prescription drug for women with irritable bowel syndrome with constipation (IBS-C). Zelnorm is for women less than 65 years old. Zelnorm was previously on the market until it was voluntarily withdrawn in 2007 due to safety concerns. A complete safety review was completed by the United States Food and Drug Administration and a committee called the Gastrointestinal Drugs Advisory Committee (GIDAC). The thorough review concluded the Zelnorm was safe for use in people with IBS-C, and in 2019 Zelnorm was reintroduced into the market.1
Zelnorm is a selective serotonin type-4 (5-HT4) receptor agonist and is the only one of its kind currently available for IBS-C. By activating this specific serotonin receptor on cells in the gastrointestinal tract, Zelnorm increases and stabilizes gut motility and intestinal secretions to increase the frequency of bowel movements. It also inhibits aspects of gut sensitivity, potentially decreasing the abdominal pain that can come along with IBS-C.1,2
The drug comes in a tablet form that is taken by mouth. It is important to take Zelnorm exactly how it is prescribed and to seek emergency medical attention if you take too much of the medicine. If there is no improvement in IBS-C symptoms after four to six weeks of treatment, Zelnorm should be discontinued.
Who should not take Zelnorm
At this time, the safety and efficacy of Zelnorm in men and children with IBS-C is not known, and these groups should not take this drug. Women over 65 years old should also not take Zelnorm. Tell your prescriber if you have other conditions and medicines you are taking.
Zelnorm may cause serious side effects including major cardiovascular events, inflammation or injury of the intestines, profuse diarrhea, and suicidal thoughts or behaviors. For this reason, people who have one or more of the following conditions should not take Zelnorm:
- History of a cardiovascular event, including a stroke, heart attack, transient ischemic attack, or angina (chest pain)
- Ischemic colitis (a lack of blood flow to the intestines) or a history of other inflammatory conditions within the intestines
- End-stage kidney disease or severe kidney problems
- Moderate or severe liver problems
- Dysfunction of any intestinal valves or a past intestinal blockage (bowel obstruction)
- History of gallbladder issues
- Past surgeries or other conditions that may have led to significant scar tissue in the abdomen
Zelnorm’s effects on an unborn baby are unknown, so Zelnorm may not be appropriate for use in pregnant women. Additionally, it is not known if Zelnorm can pass into breastmilk, and should not be used when breastfeeding. Talk to your doctor or healthcare provider if you are currently pregnant, planning to become pregnant, or breastfeeding before or while taking Zelnorm.
Possible side effects of Zelnorm
Aside from the rare, serious side effects previously listed that Zelnorm can cause, there have been other, more common and less severe side effects reported while taking the drug. These include:
People who experience severe diarrhea or changes in the mood or behavior should contact their doctor or healthcare provider immediately.1
These are not all the possible side effects of Zelnorm. Talk to your doctor about what to expect or if you experience any changes that concern you during treatment with Zelnorm.
Additional treatment options for IBS
There are other medical and alternative treatment options for IBS. Since a serotonin imbalance may cause IBS symptoms, some people may benefit from treatment with anti-depressants or other kinds of serotonin-impacting medications. Depending on an person's specific IBS symptoms, treatment with antispasmodic drugs, antibiotics, antidiarrheal drugs, or anti-anxiety therapies may be helpful.
In addition to traditional treatment options, alternative therapies and lifestyle modifications may also be beneficial for those with IBS. These include exercise, dietary changes, acupuncture, and more. It is often a trial-and-error process to determine which treatment options provide the most relief.
Before beginning treatment for IBS, tell your doctor about all your health conditions and any other drugs, vitamins, or supplements you are taking. This includes over-the-counter drugs.