Headache or joint pain may occur. If any of these effects persist or worsen, notify your doctor promptly.
Remember that your doctor has prescribed this medication because he/she has judged the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
If diarrhea occurs, it may be only temporary during the first week of treatment. If it occurs, your doctor may recommend that you drink plenty of liquids to avoid becoming dehydrated. If the diarrhea does not resolve on its own after 2 days or if you feel very weak, have severe cramping, dizziness/lightheadedness/fainting, or irregular heartbeats, stop tegaserod and tell your doctor immediately.
If you experience different or suddenly worsening stomach/abdominal pain compared to your regular IBS symptoms, with or without bloody stools, stop taking this medication and tell your doctor immediately. This could be a sign of a rare but serious intestinal problem (ischemic colitis).
Seek immediate medical attention if the following rare but very serious side effects occur: chest/jaw pain or discomfort, weakness on one side of your body, slurred speech, confusion.
An allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of an allergic reaction include: rash, itching, swelling, severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.