7 Symptoms Never to Ignore If You Have IBS

Medically Reviewed By William C. Lloyd III, MD, FACS
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  • If you're one of the 25 to 45 million Americans with irritable bowel syndrome (IBS), you no doubt are familiar with its common symptoms: abdominal pain, diarrhea, constipation, bloating and gas. Beyond IBS flares—an abrupt increase in symptoms—sometimes you may have symptoms that raise red flags and warrant a call to your doctor. Here are some IBS ’alarm’ symptoms you should never ignore, because they can indicate IBS complications or the development of another serious condition.

  • 1
    Changes in Bowel Function
    young Caucasian man holding stomach with restroom sign in background

    Some people with IBS have diarrhea as part of their illness; others experience constipation; and a third group has both symptoms, on an alternating basis. If you have noticed the basic pattern of your bowel symptoms changing recently, or if your IBS symptoms have suddenly become much more severe, this is a sign there could be something else going on. Another common IBS alarm symptom to watch for is having persistent abdominal pain that does not go away when you have a bowel movement or pass gas. If you've had changes like these, contact your doctor.

  • 2
    Blood in Your Stool
    Close-up of woman's feet on bathmat on bathroom floor

    You may notice small amounts of bright red blood in your stool. This can be due to hemorrhoids, which are not caused by IBS itself, but can be caused by constipation. (Constipation can lead to straining during bowel movements, which can aggravate or cause hemorrhoids or small tears in the anal passage leading to small amounts of bleeding.) However, large amounts of bright red blood or black, tar-colored stools can indicate other serious conditions, such as peptic ulcers. Bring any type of blood in your stool (and a sample if possible) to your doctor's attention.

  • 3
    Unexplained Weight Loss
    close-up of woman adjusting medical scale

    If you have been dropping weight without trying to, tell your doctor as soon as possible. IBS is generally not associated with weight loss; instead, researchers have found most IBS patients are either normal weight or overweight. So, if you have IBS and are experiencing weight loss, this is a red flag you might have another condition—especially if you also are having fevers. Your healthcare provider can order tests to determine why you are dropping pounds and what steps, if any, need to be taken.

  • 4
    Anemia Symptoms
    Young Asian American woman at desk with headache or migraine or fatigue

    Anemia is a common blood disorder characterized by a loss of red blood cells, resulting in fatigue. Most people who have it get it because they have an iron deficiency or a vitamin B12 deficiency. Because people with IBS have trouble absorbing dietary nutrients (due to diarrhea and constipation), they don't always get the iron or vitamin B12 they need. So, anemia can be an IBS complication. However, iron-deficiency anemia can also be a sign of blood loss from bleeding. Your doctor needs to know about this symptom to properly treat you.

  • 5
    Unexplained Vomiting
    woman vomiting in toilet

    Nausea affects 40% of women with IBS and 30% of men, but vomiting is less common—particularly excessive and recurrent vomiting. Sometimes IBS can affect your biliary system (your gallbladder and bile ducts) and cause you to vomit, as well as feel nausea and abdominal pain. But vomiting can also be a sign of other, potentially serious conditions, and should not be written off as just part of your IBS. Notify your healthcare provider if you are experiencing this symptom.

  • 6
    Difficulty Swallowing
    African America woman holding throat while taking drink of water

    Ever felt like you have a lump in your throat and can't swallow? Difficulty swallowing (dysphagia) can sometimes be caused by IBS, which can trigger spasms in your esophagus. However, dysphagia can also be caused by many other illnesses, including esophageal tumors, acid reflux or GERD (gastroesophageal reflux disease), neurological disorders (such as Parkinson's disease), and stroke. Trouble swallowing can lead to malnutrition, weight loss, dehydration, choking, or pneumonia (caused by food entering your airway). It's important to let your doctor know if you have this symptom.

  • 7
    Diarrhea That Wakes You Up at Night
    Cropped image of woman's legs sitting on toilet

    Waking up during sleep with an episode of diarrhea isn't a common IBS symptom. Generally, people with IBS who are prone to diarrhea experience it while they're awake, and often after eating something. Diarrhea during sleep—also known as nocturnal diarrhea—more often occurs due to other disorders. For example, microscopic colitis can cause this symptom in older patients. Other reasons for nocturnal diarrhea include Crohn's disease, endocrine disorders, and taking certain medications. If you have this symptom, your health provider can help determine its cause.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Jan 4
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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