Irritable Bowel Syndrome (IBS): Symptoms, Causes & Treatments

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Irritable bowel syndrome (IBS) is a common digestive system disorder, characterized by stomach pain and diarrhea or constipation. The cause differs for every patient, and the best treatment depends on the diagnosed cause.

How many people in the United States have IBS? According to the International Foundation of Functional Gastrointestinal Disorders, between 25 and 45 million people in the United States have IBS. That is almost a quarter of American adults.

Digestive diseases are nothing to be embarrassed about, but you don’t have to live with such abdominal distress. You may be able to resolve digestive issues by identifying and addressing the underlying cause.

Below, we break down everything you need to know about this condition.

At PrimeHealth, we identify and treat the root cause of your IBS symptoms, instead of masking superficial symptoms. If you live in Colorado, set up your free 15-minute consultation today.

Disclaimer: We may receive a small commission from products you purchase via links in this article.

What Is Irritable Bowel Syndrome (IBS)?

Irritable bowel syndrome is a large intestine disorder that causes recurrent abdominal pain and diarrhea or constipation over at least 6 months. IBS is associated with excess gas, spastic colon, small intestinal bacterial overgrowth (SIBO), and other health conditions — not just in the gut.

How long does IBS last? Individual flare-ups may last for just a couple of days to many months at a time. IBS symptoms must last for at least 6 months to officially be diagnosed, but this condition can last your whole life if you don’t do anything about it.

4 Subtypes of IBS

Below are the 4 types of IBS as categorized by the Rome IV Criteria:

  • Diarrhea-predominant (IBS-D) describes when diarrhea (wet or loose stool) presents in more than 25% of bowel movements while constipation presents in fewer than 25%.
  • Constipation-predominant (IBS-C) describes when constipation (hard or difficult-to-pass stool) presents in more than 25% of bowel movements while diarrhea presents in fewer than 25%.
  • Mixed, or mixed pattern (IBS-M) presents both constipation and diarrhea more than 25% of the time each.
  • Unspecified (IBS-U) covers any cases of IBS that don’t fit into the other subtypes.

Symptoms of IBS

How do you feel when you have irritable bowel syndrome? The most common symptoms of irritable bowel syndrome are bloating and cramping. You seldom feel comfortable when you’re more than a minute from a bathroom. IBS symptoms make you feel as if you’re sick to your stomach, resulting in frequent bathroom trips.

READ NEXT: Colon Cleansing: Types, Benefits, Dangers & FAQs

Distinguishing IBS vs. Other Conditions

There are several health conditions and symptoms that may be confused with IBS:

  • Menstrual cramping may be confused with abdominal cramping for women during a menstrual cycle. Most women can decipher which is which, but younger women who have only recently started menstruating may not have the same experience distinguishing between the two.
  • IBD (inflammatory bowel disease) can be tricky to differentiate from irritable bowel syndrome. IBS and IBD are separate classifications. Crohn’s disease and ulcerative colitis are examples of IBD, and both are considered more severe disorders than IBS. Extra-gastrointestinal IBD symptoms (outside the gut) include eye inflammation, joint pain, and extreme fatigue. A doctor can confirm the diagnosis of IBD with a colonoscopy and biopsies from the digestive tract.
  • Celiac disease is an autoimmune disorder where gluten causes inflammation and IBS-like symptoms. Avoiding gluten and strengthening your immune system should help.
  • Lactose intolerance describes the lack of lactase enzyme which digests lactose, AKA milk sugar found in dairy products. This intolerance may contribute to IBS symptoms, but it is easier to prevent lactose intolerance-caused abdominal upset. Simply find dairy alternatives or take lactase supplements.
  • Diverticulitis is when pouches or pockets form in weak, sagging parts of your lower colon, leading to inflammation that can cause symptoms similar to IBS.

Diagnosing Irritable Bowel Syndrome

To diagnose IBS, doctors refer to the Rome IV Criteria. A proper diagnosis of IBS is when you have experienced:

  • Recurring abdominal pain for 6 or more months, or any two of the following three symptoms in the past 3 months
  • Pain or relief related to bowel movements
  • Change in frequency of bowel movements
  • Change in consistency of bowel movements

The upcoming Rome V Criteria is due to come out in 2026, possibly changing the standard diagnostic procedures for IBS.

What to Rule Out

During the diagnostic process, your healthcare provider may wish to rule out any of the following disorders:

  • Small intestinal bacterial overgrowth (SIBO)
  • IBD
  • Anemia
  • Colon cancer
  • Carcinoid syndrome
  • Menstrual changes
  • Food allergies
  • Leaky gut
  • Chronic inflammation
  • Chronic stress
  • Parasites
  • Yeast overgrowth
  • Antibiotic overuse
  • Hormone imbalance

How to Test

IBS is often a “diagnosis of exclusion,” meaning that other known causes for gastrointestinal distress need to be ruled out before you get an official IBS diagnosis from a gastroenterologist or other healthcare professional.

Before any lab tests, your doctor may ask about your personal medical history and family history. They may also perform a rectal exam.

Keeping an up-to-date food diary may help you and your doctor nail down your unique IBS triggers.

A colonoscopy, upper endoscopy, stool test, or CT scan may be required to rule out conditions besides IBS.

At PrimeHealth, my team and I run SIBO tests for all our patients with IBS since SIBO is a common cause of its symptoms. The majority of the time, the test comes back positive.

Glucose and lactulose breath tests are less invasive than blood tests and can effectively identify SIBO.

  • A methane-positive test usually indicates a constipation-dominant IBS.
  • A hydrogen-positive test usually indicates diarrhea-dominant IBS.
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Causes of IBS

The main causes of IBS are different for every patient. Common causes include SIBO, hormonal changes, chronic inflammation, chronic stress, infections, antibiotic overuse, nervous system dysfunction, and cancer — in rare cases.

Talk to your doctor about identifying your unique underlying cause so that you can treat those root causes instead of simply masking symptoms.

Risk Factors for IBS

The most common risk factors for IBS include:

  • Stress
  • Younger age
  • Female sex
  • Stomach flu (gastroenteritis)
  • Smoking
  • Excessive alcohol use
  • Diabetes
  • Mental health problems
  • Family history of IBS

Common IBS Triggers

IBS flare-ups may be triggered by:

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IBS Treatments

The most common and effective treatment options for irritable bowel syndrome may surprise you. Rifaximin, lifestyle and dietary changes, fecal transplant, supplements, and limited antibiotic use may get rid of your pesky IBS symptoms.

We have found that IBS can be cured in most cases. Yes, that is a controversial claim to make. But our patients prove it to be true.


IBS medications can support the recovery and reversal of this condition. Some address underlying causes while others mask symptoms. Not all medications are created equally, and you should always pay attention to side effects.

Below are the most common medications to help with IBS:

  • Rifaximin is the generic of Xifaxan, an FDA-approved antibiotic to treat IBS-D.
  • Neomycin is a safe antibiotic for methane-dominant IBS.
  • Antispasmodics like Bentyl (dicyclomine) may help with cramping.
  • Laxatives are meant to treat constipation.
  • Antidiarrheals like loperamide (Imodium) are meant to treat diarrhea.
  • Tricyclic antidepressants or SSRIs (selective serotonin reuptake inhibitors) may improve mental health and ease physical pain. These antidepressants may lead to serious side effects.
  • Metronidazole or tinidazole are antiparasitic antibiotics that address parasites as an underlying cause.
  • Prokinetics (AKA promotility agents) are benign medications that help your digestive tract’s motility, which is useful in stubborn IBS cases. Some examples are ginger, low-dose naltrexone, and prucalopride.
  • Biofilm disruptors may weaken harmful bacteria. Bacteria often form a biofilm to adapt to antibiotics, so a biofilm disruptor may be needed to neutralize bacterial biofilm defenses.

Rifaximin is the only medication we prescribe for hydrogen-dominant IBS. While many insurance companies will not pay its high price tag, we use pharmacies in Canada to obtain the generic form at a reasonable price.


Research reveals that specific herbal blends may be as effective as Rifaximin in treating SIBO. For many patients, the all-natural route is the best one. Dietary supplements are a vital part of natural IBS treatment.

The following dietary supplements may help treat irritable bowel syndrome:


What is a typical IBS diet? The low-FODMAP diet is typically beneficial for IBS patients. My team and I recommend a temporary low-FODMAP elimination diet as part of nearly every IBS management plan for PrimeHealth patients. We will slowly reintroduce foods to see what you can handle and what may be triggering your IBS.

FODMAP stands for “fermentable oligosaccharides, disaccharides, monosaccharides, and polyols,” and they’re basically fermentable carbs. They can trigger bloating and other IBS symptoms. Low-FODMAP is not meant to be followed for more than a few months.

What foods usually trigger IBS? Avoid these IBS-triggering foods on the low-FODMAP diet:

  • Wheat
  • Rye
  • Dairy
  • Beans
  • Garlic (contain fructans)
  • Onions (contain fructans)
  • Fruit (because of fructose)
  • Asparagus
  • Brussels sprouts
  • Cauliflower
  • Mushrooms
  • Snow peas
  • Agave nectar
  • Sugar alcohols
  • Ripe bananas

Lifestyle Changes

Certain lifestyle changes can reduce your IBS symptoms or prevent IBS flare-ups:

  • Stress relief is a great way to lower your risk for irritable bowel syndrome. Talk therapy, hypnotherapy, a full night’s sleep, yoga, and spending time outside can all relieve stress.
  • Exercise may help treat IBS. This clinical trial revealed that physically active people are significantly less likely to suffer from IBS than inactive people.
  • Intermittent fasting may help relieve IBS. If you’re eating too much too quickly, your digestive tract doesn’t have time to process the food properly. Aim for a 12-hour fasting window, then work your way to 14-16 hours between dinner and breakfast.
  • Cognitive-behavioral therapy helps IBS patients train their bowels, small intestine, and rectum to move waste when the patient wants to — not when the body decides to.
  • Detox is a great way to make sure your gut is not full of heavy metals, pesticides, and excess estrogen. Detoxification can take many forms, but eating organic and checking for mold in your home are two great ways to avoid toxins.

Complications of Untreated IBS

Several possible complications can arise when you live with untreated irritable bowel syndrome, including:

Long-Term Outlook for IBS

You can reverse irritable bowel syndrome by treating the root cause of your IBS! Patients have come through our doors who have had IBS for 10 years. Nothing worked for them until we identified and treated the underlying cause — then we saw huge improvements in weeks.

Live in Colorado and want to regain control over your health? Schedule your no-cost consultation today!


  1. Huang, K. Y., Wang, F. Y., Lv, M., Ma, X. X., Tang, X. D., & Lv, L. (2023). Irritable bowel syndrome: epidemiology, overlap disorders, pathophysiology and treatment. World Journal of Gastroenterology, 29(26), 4120.
  2. Won, E., & Kim, Y. K. (2016). Stress, the autonomic nervous system, and the immune-kynurenine pathway in the etiology of depression. Current neuropharmacology, 14(7), 665-673.
  3. Fasano, A. (2020). All disease begins in the (leaky) gut: Role of zonulin-mediated gut permeability in the pathogenesis of some chronic inflammatory diseases. F1000Research, 9
  4. Jadallah, K. A., Nimri, L. F., & Ghanem, R. A. (2017). Protozoan parasites in irritable bowel syndrome: a case-control study. World journal of gastrointestinal pharmacology and therapeutics, 8(4), 201.
  5. Bonaz, B., Bazin, T., & Pellissier, S. (2018). The vagus nerve at the interface of the microbiota-gut-brain axis. Frontiers in neuroscience, 12, 49.
  6. Reding, K. W., Cain, K. C., Jarrett, M. E., Eugenio, M. D., & Heitkemper, M. M. (2013). Relationship between patterns of alcohol consumption and gastrointestinal symptoms among patients with irritable bowel syndrome. The American journal of gastroenterology, 108(2), 270.
  7. Filip, M., Tzaneva, V., & Dumitrascu, D. L. (2018). Fecal transplantation: digestive and extradigestive clinical applications. Clujul Medical, 91(3), 259.
  8. Chedid, V., Dhalla, S., Clarke, J. O., Roland, B. C., Dunbar, K. B., Koh, J., … & Mullin, G. E. (2014). Herbal therapy is equivalent to rifaximin for the treatment of small intestinal bacterial overgrowth. Global advances in health and medicine, 3(3), 16-24.
  9. Mu, Q., Kirby, J., Reilly, C. M., & Luo, X. M. (2017). Leaky gut as a danger signal for autoimmune diseases. Frontiers in immunology, 8, 598.
  10. El Amrousy, D., Hassan, S., El Ashry, H., Yousef, M., & Hodeib, H. (2018). Vitamin D supplementation in adolescents with irritable bowel syndrome: Is it useful? A randomized controlled trial. Saudi journal of gastroenterology: official journal of the Saudi Gastroenterology Association, 24(2), 109.
  11. Williams, C. E., Williams, E. A., & Corfe, B. M. (2018). Vitamin D status in irritable bowel syndrome and the impact of supplementation on symptoms: what do we know and what do we need to know?. European journal of clinical nutrition, 72(10), 1358-1363.
  12. Liu, X., Ma, Z., Zhang, J., & Yang, L. (2017). Antifungal compounds against candida infections from traditional Chinese medicine. BioMed research international, 2017.
  13. Duntas, L. H. (2015). The role of iodine and selenium in autoimmune thyroiditis. Hormone and Metabolic Research, 47(10), 721-726.
  14. Zou, Y., Xiang, Q., Wang, J., Peng, J., & Wei, H. (2016). Oregano essential oil improves intestinal morphology and expression of tight junction proteins associated with modulation of selected intestinal bacteria and immune status in a pig model. BioMed research international, 2016.
  15. Esposito, G., Filippis, D. D., Cirillo, C., Iuvone, T., Capoccia, E., Scuderi, C., … & Steardo, L. (2013). Cannabidiol in inflammatory bowel diseases: a brief overview. Phytotherapy Research, 27(5), 633-636.
  16. Sharkey, K. A., & Wiley, J. W. (2016). The role of the endocannabinoid system in the brain–gut axis. Gastroenterology, 151(2), 252-266.
  17. Borrelli, F., Fasolino, I., Romano, B., Capasso, R., Maiello, F., Coppola, D., … & Izzo, A. A. (2013). Beneficial effect of the non-psychotropic plant cannabinoid cannabigerol on experimental inflammatory bowel disease. Biochemical pharmacology, 85(9), 1306-1316.
  18. Gibson, P. R., & Shepherd, S. J. (2005). Personal view: food for thought–western lifestyle and susceptibility to Crohn’s disease. The FODMAP hypothesis. Alimentary pharmacology & therapeutics, 21(12), 1399-1409.
  19. Hirotsu, C., Tufik, S., & Andersen, M. L. (2015). Interactions between sleep, stress, and metabolism: From physiological to pathological conditions. Sleep Science, 8(3), 143-152.
  20. Thompson, C. W., Roe, J., Aspinall, P., Mitchell, R., Clow, A., & Miller, D. (2012). More green space is linked to less stress in deprived communities: Evidence from salivary cortisol patterns. Landscape and urban planning, 105(3), 221-229.
  21. Johannesson, E., Simrén, M., Strid, H., Bajor, A., & Sadik, R. (2011). Physical activity improves symptoms in irritable bowel syndrome: a randomized controlled trial. American Journal of Gastroenterology, 106(5), 915-922.
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