Irritable bowel syndrome (IBS) doesn't usually cause nausea and vomiting. Typical symptoms of IBS include abdominal pain, gas and bloating, and diarrhea or constipation. Though some people with IBS may also experience nausea, this symptom is not common and is usually related to another condition such as gastrointestinal reflux disease (GERD) or gallbladder problems.
Other symptoms may also suggest a health problem other than IBS. These symptoms don't necessarily mean you don't have IBS, though. Tell your healthcare provider about any symptoms you have on a regular basis, even if they are not on this list.
This article looks at some of the symptoms that may be related to a health problem other than IBS.
Vomiting on a Regular Basis
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Vomiting is not a typical symptom of IBS. When people who have IBS experience nausea and vomiting, it is probably not because of their IBS. However, nausea and vomiting can be a symptom of conditions that often occur alongside IBS, such as gastroesophageal reflux disease (GERD) and functional dyspepsia.
If you experience frequent vomiting, tell your healthcare provider. If you are having uncontrollable vomiting or are vomiting up blood, see a doctor at once.
If you have functional dyspepsia, you may also have additional symptoms like:
- Feeling full quickly
- Bloating
- Pain in the middle of your upper abdomen after eating
GERD can cause additional symptoms such as:
- A burning sensation in the upper abdomen
- Indigestion
Medications you take to treat your IBS symptoms such as Amitiza (lubiprostone) may also cause nausea and/or vomiting as a side effect.
Vomiting that does not happen with other signs of disease could be a condition called cyclic vomiting disorder (CVS). If you have vomiting without other symptoms, talk to your doctor.
Gas and Bloating Within 90 Minutes of Eating
Intestinal gas and bloating are common IBS symptoms. The timing of the these symptoms, though, is important.
Carbohydrates are substances in food that provide your body with energy. They include sugars, starches, and fiber. It usually takes about 90 minutes for undigested carbohydrates to reach your large intestine.
Once there, gut bacteria start breaking them down. This is called fermentation. Fermentation produces gas.
You should not start to feel gassy before that 90-minute mark. If you do, it could be because you have too much bacteria in your small intestine.
This condition is called small intestinal bacterial overgrowth (SIBO). SIBO is diagnosed with a hydrogen breath test. It can be treated with select antibiotics.
If you experience gas and bloating within 1.5 hours of eating, talk to your doctor. This doesn't necessarily mean your doctor was wrong about your IBS. It just means it might be worthwhile to be tested for SIBO.
Diarrhea Right After Eating
Frequent bouts of diarrhea are a common IBS symptom. This symptom is also common with inflammatory bowel disease (IBD), a group of conditions that cause inflammation of the intestines. It is also seen in celiac disease, which is an immune reaction to a protein found in wheat and other grains.
The simple act of eating can cause contractions in your intestines. This can lead to diarrhea.
A couple of other conditions could also cause this symptom. These conditions are less common. If you have a sudden, immediate diarrhea right after eating, talk to your doctor. Your doctor may want to consider:
- Bile acid malabsorption, when too much bile acid reaches your large intestine
- Dumping syndrome, when food moves too quickly from your stomach to the small intestine
These conditions are relatively rare. It is still possible that diarrhea after eating is a symptom of your IBS. Still, it may be a good idea to talk to your doctor about other possibilities.
Pain Unrelated to Bowel Movements
In people with IBS, the criteria for diagnosis says abdominal pain should be related to bowel movements.
Many IBS patients say this is not always true. But for the most part, people with IBS feel like their pain has something to do with their diarrhea or constipation.
If you have pain you don't think is related to your bowel movements, talk to your doctor. It may still be IBS, but it is worth looking at other possibilities.
If you have an IBS diagnosis but you think your pain is not typical of IBS, talk to your doctor at once. Persistent pain should always be evaluated by a doctor.
Symptoms Set Off by Eating Wheat
Gluten is a protein found in wheat and some other grains. For many people, foods that contain gluten can cause IBS-like symptoms.
That is why doctors recommend that people with IBS should also be tested for celiac disease. This test is only conclusive if you are eating foods that contain gluten.
Celiac disease can cause other serious health problems, so it is important to know if you have it.
Even if you do not have celiac disease, eating wheat may trigger IBS symptoms. You may have a condition known as non-celiac gluten sensitivity.
You may also be reacting to fructan, a kind of carbohydrate found in grains and some fruits and vegetables. Your doctor can guide you through an elimination diet to determine if any foods are triggering your symptoms.
Blood in Stools
Blood on or in the stool is not a symptom of IBS. Sometimes blood in the stool comes from hemorrhoids. Hemorrhoids are swollen veins that can develop in your anus and lower rectum.
Blood in the stool can also be a symptom of other more serious problems. This includes IBD or colon cancer.
If you see blood in the toilet after a bowel movement and it is not menstrual blood, see a doctor as soon as possible.
Unexplained Weight Loss
IBS may cause some weight loss, especially if you avoid food for fear of triggering symptoms. Significant, unexplained weight loss, though, is not a symptom of IBS. If you have this kind of weight loss, it may be a symptom of a more serious health problem.
If you have a poor appetite and it is not because you're afraid of eating trigger foods, see a doctor. This is not an IBS symptom.
Running Fevers
IBS should not cause you to run a fever. Recurrent fevers have other causes, including:
- Infections
- Inflammatory conditions
- Autoimmune conditions, when your immune system attacks healthy tissue by mistake
- Cancer
If you experience recurrent fevers, talk to your doctor right away.
Deep, Persistent Fatigue
Fatigue is not the same thing as feeling sleepy. Fatigue is extreme tiredness that can be both physical and emotional.
Many people with IBS say they often lack energy. Fatigue, though, is not a symptom of IBS. If you have deep, persistent feelings of fatigue, let your doctor know.
Summary
Symptoms of IBS can include abdominal pain, gas, bloating, and diarrhea and/or constipation. Other symptoms may be related to a different condition.
If you have gas and bloating within 90 minutes of eating, diarrhea right after you eat, or pain that does not seem related to your bowel movements, talk to your doctor.
People who get IBS-like symptoms after eating wheat and other foods that contain gluten should be tested for celiac disease.
Other symptoms that are not associated with IBS include blood in the stool, frequent vomiting, unexplained weight loss, fever, and fatigue. If you have any of these symptoms, see a doctor right away.