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Zelnorm Side Effects

Generic Name: tegaserod

Note: This page contains side effects data for the generic drug tegaserod. It is possible that some of the dosage forms included below may not apply to the brand name Zelnorm.

For the Consumer

Applies to tegaserod: oral tablet

As well as its needed effects, tegaserod (the active ingredient contained in Zelnorm) may cause unwanted side effects that require medical attention.

Major Side Effects

If any of the following side effects occur while taking tegaserod, check with your doctor immediately:

More common:
  • Diarrhea
  • stomach pain
Less common:
  • Dizziness
  • feeling of warmth
  • itching skin
  • redness of the face, neck, arms and occasionally, upper chest
  • swelling or puffiness of face
Incidence not known:
  • Black, tarry stools
  • bloody diarrhea
  • bloody stools
  • constipation
  • fainting
  • indigestion
  • nausea
  • new or worsening abdominal pain
  • rectal bleeding
  • severe stomach pain with nausea and vomiting
  • vomiting

If any of the following symptoms of overdose occur while taking tegaserod, get emergency help immediately:

Symptoms of overdose:
  • Bloated, full feeling
  • chills
  • cold sweats
  • confusion
  • dizziness, faintness, or lightheadedness when getting up from lying or sitting position
  • excess air or gas in stomach or intestines
  • headache
  • passing gas

Minor Side Effects

Some tegaserod side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:

Less common or rare:
  • Back pain
  • disease or abnormality of the joint
  • headache, severe and throbbing
  • leg pain

For Healthcare Professionals

Applies to tegaserod: oral tablet


Cardiovascular side effects have included hypotension, angina pectoris, syncope, arrhythmia, bundle branch block, supraventricular tachycardia, and flushing. A case of myocardial infarction has been reported.[Ref]

Myocardial infarction has been reported in a 64-year-old male after receiving two doses of tegaserod 6 mg.[Ref]

Nervous system

Nervous system side effects have included headache, dizziness, migraine, insomnia, vertigo, and Raynaud's phenomenon.[Ref]


Gastrointestinal side effects have included abdominal pain, diarrhea, nausea, flatulence, abdominal distention and pain, vomiting, dyspepsia, gastritis, gastroesophageal reflux, hemorrhoids, and proctalgia. Irritable colon, fecal incontinence, tenesmus, increased appetite, eructation, appendicitis, bilirubinemia, subileus, sphincter of Oddi spasm, bile duct stone, ischemic colitis, mesenteric ischemia, gangrenous bowel, rectal bleeding, and increases in abdominal surgeries, primarily cholecystectomies, have also been reported; however, causality was not clearly established.[Ref]


Hepatic side effects have included increased SGOT and SGPT. Hepatitis, elevation in ALT, AST, and bilirubin have been reported during postmarketing experience.[Ref]


Metabolic side effects have included increase in appetite, hypokalemia and hypovolemia secondary to diarrhea, and increased creatine phosphokinase.[Ref]


Musculoskeletal side effects have included back pain, arthropathy, and myalgia. Other effects, regardless of causality, have included cramps.[Ref]


Oncologic side effects have included breast carcinoma.[Ref]


Psychiatric side effects have included attempted suicide, impaired concentration, emotional lability, increased appetite, sleep disorder and depression.[Ref]


Respiratory side effects have included asthma.[Ref]


Dermatologic side effects have included pruritus. Alopecia has been reported during postmarketing experience.[Ref]


Endocrine side effects have included increased sweating.[Ref]


Genitourinary side effects have included frequent micturition, polyuria, urinary tract infection, ovarian cyst, miscarriage, dysmenorrhea, and menorrhagia.[Ref]


Renal side effects have included renal pain and albuminuria.[Ref]


Side effects affecting the body as a whole have included accidental trauma (3% vs. 2% for placebo) and leg pain (1% vs. less than 1% for placebo). Other effects, regardless of causality, have included pain and facial edema.[Ref]


1. Busti AJ, Murillo JR Jr, Cryer B "Tegaserod-induced myocardial infarction: case report and hypothesis." Pharmacotherapy 24 (2004): 526-31

2. Morganroth J, Ruegg PC, Dunger-Baldauf C, Appel-Dingemanse S, Bliesath H, Lefkowitz M "Tegaserod, a 5-hydroxytryptamine type 4 receptor partial agonist, is devoid of electrocardiographic effects." Am J Gastroenterol 97 (2002): 2321-7

3. "Product Information. Zelnorm (tegaserod)." Novartis Pharmaceuticals, East Hanover, NJ.

4. Bertoli R, Girardin F, Russmann S, Lauterburg BH "Raynaud's phenomenon induced by drugs acting on neurotransmission: two cases under reboxetine and one under tegaserod." Eur J Clin Pharmacol 58 (2003): 717

It is possible that some side effects of Zelnorm may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.