How ZELNORM Works   |   Mechanism of Action


See how ZELNORM stimulates serotonin receptors to relieve symptoms of IBS-C.

ZELNORM acts by binding to 5-HT4 receptors, resulting in accelerated peristalsis and reduced sensory response.2,3

ZELNORM is the only prokinetic agent that stimulates serotonin receptors for IBS-C treatment

As a 5-HT4 agonist, ZELNORM works throughout the GI tract to address constipation, abdominal pain, and bloating of IBS-C1

  • Stimulates peristaltic reflex and intestinal secretion
  • Inhibits visceral sensitivity
  • Enhances basal motor activity
  • Normalizes impaired motility throughout the GI tract


ZELNORM (tegaserod) is indicated for the treatment of adult women less than 65 years of age with irritable bowel syndrome with constipation (IBS-C).

Important Safety Information

ZELNORM should be used in females under 65 years of age who do not have a history of ischemic cardiovascular disease and who have no more than one CVD risk factor. CVD risk factors are defined as active smoking, current hypertension/history of antihypertensive treatment, current hyperlipidemia/history of lipid-lowering medication, history of diabetes mellitus, age ≥55 years, or obesity (BMI >30 kg/m2).


ZELNORM is contraindicated in patients with:

  • History of myocardial infarction (MI), stroke, transient ischemic attack (TIA), or angina
  • History of ischemic colitis or other forms of intestinal ischemia
  • Severe renal impairment (eGFR< 15 mL/min/1.73 m2) or end-stage renal disease
  • Moderate and severe hepatic impairment (Child-Pugh B or C)
  • History of bowel obstruction, symptomatic gallbladder disease, suspected sphincter of Oddi dysfunction, or abdominal adhesions
  • Hypersensitivity to ZELNORM

Warnings and Precautions

Cardiovascular Ischemic Events, Including Major Adverse Cardiovascular Events (MACE): Stroke, MI, and cardiovascular death have been reported in adults taking ZELNORM who had an increased risk of developing an adverse cardiovascular event based on their medical history.

Female patients less than 65 years of age should be assessed for a history of cardiovascular disease and cardiovascular risk factors prior to treatment with ZELNORM.

Discontinue ZELNORM in patients who experience an MI, stroke, TIA, or angina. Evaluate the risks and benefits of continued use of ZELNORM in patients who develop evidence of cardiovascular ischemic heart disease (e.g., coronary artery disease) and/or experience changes in health status that could increase cardiovascular risk during treatment with ZELNORM.

Ischemic Colitis: Ischemic colitis and other forms of intestinal ischemia have been reported postmarketing in patients receiving ZELNORM. Discontinue ZELNORM in patients who develop symptoms of ischemic colitis, such as rectal bleeding, bloody diarrhea, or new or worsening abdominal pain.

Volume Depletion Associated with Diarrhea: In postmarketing experience, serious consequences of diarrhea including hypovolemia, hypotension, and syncope have been reported in patients treated with ZELNORM. Avoid use of ZELNORM in patients who are currently experiencing or frequently experience diarrhea. Instruct patients to discontinue ZELNORM and contact their healthcare provider if severe diarrhea, hypotension, or syncope occur.

Suicidal Ideation and Behavior: Monitor all ZELNORM-treated patients for clinical worsening of depression and emergence of suicidal thoughts and behaviors, especially during the initial few months of treatment. Counsel family members and caregivers of patients to monitor for changes in behavior and to alert the healthcare provider. Instruct patients to immediately discontinue ZELNORM and contact their healthcare provider if their depression is persistently worse or they are experiencing emergent suicidal thoughts or behaviors.

Common Adverse Reactions (incidence >2% and greater than placebo)

The most common adverse reactions in 3 placebo-controlled trials of ZELNORM in female IBS-C patients less than 65 years of age: headache (14% vs 10% placebo), abdominal pain (11% vs 10%), nausea (8% vs 7%), diarrhea (8% vs 3%), flatulence (6% vs 5%), dyspepsia (4% vs 3%), and dizziness (4% vs 3%).

Use in Specific Populations

  • Pregnancy: Safety and effectiveness not established
  • Lactation: Breastfeeding not recommended
  • Pediatric use: Safety and effectiveness not established
  • Geriatric use: Not indicated for patients 65 years of age and older
  • Severe renal conditions: Contraindicated
  • Moderate to severe hepatic conditions: Contraindicated

Please click here for full Prescribing Information.

Indication and Important Safety Information
References: 1. ZELNORM (tegaserod) [package insert]. Covington, LA: Alfasigma USA, Inc. 2019. 2. Beattie DT, Smith JAM, Marquess D, et al. The 5-HT4 receptor agonist, tegaserod, is a potent 5-HT2B receptor antagonist in vitro and in vivo. Br J Pharmacol. 2004;143(5):549-560. 3. Li Y, Nie Y, Xie J, et al. The association of serotonin transporter genetic polymorphisms and irritable bowel syndrome and its influence on tegaserod treatment in Chinese patients. Dig Dis Sci. 2007;51(11):2942-2949.