Irritable bowel syndrome (IBS) affects up to 23% of the global population and is one of the most common gastrointestinal (GI) disorders that drive people to seek healthcare. Characterized by chronic abdominal pain and changes in bowel habits, IBS symptoms significantly interfere with patients' quality of life. Conventional therapy aims to provide symptom palliation, but often these treatments are expensive (IBS-related healthcare costs account for up to $10 billion annually) and insufficient, leaving patients wanting more. A functional approach to IBS management can assist in providing desired answers and results.
What is IBS-Constipation (IBS-C)
IBS is a functional disorder related to incohesive brain and gut signaling, causing visceral hypersensitivity (a lower pain threshold of internal organs) and intestinal dysmotility (changes in intestinal muscle contraction). Functional GI disorders (FGID) are challenging to diagnose and treat because there are no observable changes to anatomy or conventional lab values. (1)
IBS is diagnosed by the ROME IV Criteria when all other pathology has been ruled out. It is a clinical diagnosis characterized by abdominal pain at least once weekly for at least three months, associated with two or more of the following:
- Related to and improved by defecation
- Associated with a change in stool frequency
- Associated with a change in stool appearance
IBS is subcategorized based on the predominance of stool type: constipation, diarrhea, or mixed. Constipation is defined as bowel movements that are infrequent and/or difficult to pass. With the IBS-Constipation (IBS-C) subtype, more than one-quarter of abnormal stools are hard and lumpy. (1)
IBS-C Signs & Symptoms
Predominant IBS-C digestive symptoms include (3):
- Abdominal pain worse after meals and better after a bowel movement
- Mucus in stool
- The feeling of incomplete evacuation
Additionally, you may have extraintestinal symptoms and co-occurring conditions like:
- Brain fog
- Temporomandibular joint disorder (TMJ)
- Interstitial cystitis
Risk Factors for IBS-C?
Factors that may increase your risk for IBS-C include:
- Age under 50
- Female sex
- Estrogen therapy
- Family history of IBS
However, having one or more risk factors does not guarantee you will develop IBS-C.
What Causes IBS-C?
The underlying cause of IBS-C is not entirely understood, but there are emerging theories for the driving mechanisms behind its etiology including:
IBS symptoms may arise following exposure to an acute intestinal infection. This is known as post-infectious IBS (PI-IBS) and is characterized by the persistence of GI symptoms despite clearance of the infectious pathogen. Residual mucosal inflammation and persistent changes in immune cell activity increase the risk of developing IBS by six-fold for at least two years after a GI infection. (2)
Intestinal dysbiosis, an imbalance in healthy bacteria and fungi, commonly leads to changes in digestive function and mental health. This is partly due to intestinal inflammation and permeability contributing to IBS symptoms. But gut bacteria are also responsible for producing 95% of the body's serotonin, which influences mood and plays a significant role in GI motility, sensation, and secretions. Reduced blood levels of serotonin have been associated with IBS-C. (2, 3)
Small intestinal bacterial overgrowth (SIBO) is an overgrowth of bacteria in the small intestine and is a common cause of IBS-like digestive symptoms. It is conventionally overlooked in the conventional medicine model, but studies estimate that it can affect up to 78% of patients with IBS. (9)
Nervous System Dysregulation
The three distinct divisions of the autonomic nervous system (sympathetic, parasympathetic, and enteric) are responsible for regulating the involuntary aspects of the body's physiology. There is always a balance between processes in the body that favor our stress "fight or flight" and our relaxed "rest and digest" responses. Acute stressful events, chronic stress, and trauma all push our body towards "fight or flight" reflexes and increase the risk of IBS. (2)
Adverse food reactions are very common, affecting up to 20% of the general population and 65% of IBS patients. Food sensitivities, contributors to GI inflammation and permeability, are often reported as aggravators of IBS symptoms.
Functional Medicine Labs to Test for Root Cause of IBS-Constipation
- A complete blood count (CBC) can screen for signs of past infection if suspicious of PI-IBS.
- An at-home lactulose breath test measures hydrogen and methane gasses produced by resident bacteria in the intestines and can diagnose SIBO. An overproduction of methane gas is most commonly associated with IBS-C.
- A comprehensive stool profile can help identify various contributing factors to IBS, including large intestinal dysbiosis, digestive enzyme insufficiencies, and intestinal inflammation.
- Food sensitivities can be challenging to diagnose without testing because the triggering food(s) often cause delayed reactions, with symptoms developing up to 72 hours after ingestion. A food sensitivity panel can identify IBS-trigger foods and is a useful tool in customizing elimination diets that are routinely part of IBS-C treatment protocols.
- Cortisol is the body's primary stress hormone. Salivary cortisol testing measures cortisol levels at different time points throughout the day to map cortisol's secretion pattern. This test can help diagnose imbalances in the stress responses contributing to IBS-C.
Other Labs to Check
To rule out conditions that mimic IBS, you may consider ordering the following tests:
- Comprehensive Metabolic Panel (CMP): screens for gallbladder and liver dysfunction
- Comprehensive Thyroid Panel: screens for hypothyroidism and subclinical hypothyroidism (SCH); utilizing a comprehensive panel versus TSH alone ensures that hypothyroid cases are not missed
- 40% of women with IBS report that menstruation affects their IBS symptoms. If you experience other symptoms related to your menstrual cycle, the DUTCH test can detect hormonal imbalances contributing to menstrual and GI symptoms.
Conventional Treatment for IBS-C
Conventional therapy goals include symptom palliation and improvement of quality of life.
An antibiotic trial of metronidazole or neomycin may be prescribed for IBS-C. (4)
In addition, medications that encourage regular bowel movements and decrease abdominal discomfort include laxatives, GI motility agents, antispasmodics, and tricyclic antidepressants. (5) These prescriptive motility agents do not treat the root cause of the problem and can often make the patient's IBS-C worse over time.
Functional Medicine Branch Treatment for IBS-C
Quick-fix, or what we like to call branch treatments, are often necessary to provide fast relief from IBS flares.
Short Term Therapeutic Diets for IBS-Constipation
Short-term therapeutic diets such as the Low-FODMAP Diet, Bi-Phasic Diet, Specific Carbohydrate Diet, and GAPS Diet can be helpful, especially if SIBO is an underlying factor for your IBS. These diets aim to eliminate foods that feed intestinal bacteria and alleviate GI symptoms.
Quick Acting Supplements for IBS-Constipation
There are many alternative natural options to pharmaceuticals that are effective at managing abdominal pain, gas, bloating, and constipation. Options include:
- Peppermint oil relaxes the smooth muscle of the GI tract, easing abdominal pain and cramping. Enteric-coated preparations are best tolerated to avoid causing heartburn and stomach irritation.
- Supplementation with melatonin at bedtime may reduce abdominal pain and can be helpful with resetting circadian sleep rhythms and promoting healthy sleep and stress responses.
- Magnesium in the oxide or citrate form acts as an osmotic laxative, drawing water into the intestine to help alleviate constipation.
- Treatment with Chinese herbal medicine (CHM) has been shown to improve symptom scores, effectively reducing the extent to which IBS interferes with daily life.
- Abdominal massage may help to reeducate the muscles that control bowel movements and reduce symptoms of constipation and generalized pelvic and abdominal pain.
Functional Medicine Root Cause Treatment for IBS-C
There is no one-size-fits-all approach to IBS-C treatment. A treatment protocol should be tailored to each patient's history, lab results, and preferences. Considering the possible underlying causes of IBS, this article will discuss some of the routinely utilized natural treatment options.
Fiber (both soluble and insoluble) supports healthy bowel movements. A healthy diet that includes fruits, vegetables, and whole grains will aid in meeting dietary fiber goals. Flax seed, acacia powder, guar gum, and psyllium husk can all be used to supplement dietary fiber as needed.
Other dietary habits that can promote GI health include:
- Eat meals at a slowed pace and chew food thoroughly.
- Listen to your hunger and satiety signals.
- Avoid refined carbohydrates and trans fats.
- Incorporate more essential fatty acids from nuts, seeds, and fish
- Avoid sugar substitutes (i.e., xylitol, mannitol, and sorbitol)
- Limit caffeine and alcohol
For some patients, an elimination diet followed for 6-8 weeks can eliminate triggers perpetuating intestinal inflammation. The elimination diet should be done in conjunction with other gut-healing therapies with the ultimate goal of successfully reintroducing eliminated foods into the diet.
Herbs & Supplements for IBS-Constipation
Antimicrobial herbs and probiotics both have a role in addressing intestinal dysbiosis. Combined herbal antimicrobial formulas containing berberine, oregano, allicin, thyme, and wormwood are often used to treat bacterial and yeast overgrowth.
Ginger is commonly used for gas and bloat, but a lesser-known therapeutic benefit of ginger is its effects on GI motility. Gingerol, a natural component of ginger root, benefits gastrointestinal motility ― the rate at which food exits the stomach and continues along the digestive process. Eating ginger accelerates gastric emptying and stimulates antral contractions, which can help patients suffering from SIBO, slow digestion, and constipation.
Probiotic therapy with Lactobacillus and Bifidobacterium species, along with the beneficial yeast Saccharomyces boulardii, restores the balance of beneficial microbes, decreases intestinal inflammation, and reduces IBS symptom scores. (6-9)
Factors leading to IBS can also contribute to gut "leakiness." Failure to heal the intestinal barrier can leave you with unresolved GI symptoms and food intolerances. Gut healing protocols may include vitamins A and D, zinc carnosine, L-glutamine, butyrate, digestive enzymes, and licorice.
Lifestyle Changes for IBS-Constipation
Prevent dehydration, which exacerbates constipation, by drinking plenty of water and adding electrolytes. The National Academy of Medicine (NAM) suggests that men drink 13 cups and women drink 9 cups daily. You may need to drink more water to compensate for exercise, caffeine intake, and hot weather.
Manage stress effectively. Begin by removing the stressors that you are able. Implementing habits like a consistent sleep routine, exercise, and mindfulness will help to cope with stress.
Regular exercise can help constipation. This 2018 study concluded that low- to moderate-intensity activity could relieve IBS-C symptoms.
Your doctor may recommend a bowel retraining program to help regain control of your bowel movements. Bowel retraining supports the normalization of stool consistency and regularity.
IBS-C is a complex, multifactorial GI condition that significantly interferes with life. While a conventional approach to treatment may be effective at managing symptoms in the short-term, discontinuation of prescriptions typically results in the recurrence of symptoms. A holistic approach to IBS-C utilizes functional testing and a combination of modalities to identify and correct imbalances at the root of GI dysfunction.
Lab Tests in This Article
1. Definition & Facts for Irritable Bowel Syndrome. (2022, July 23). National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/digestive-diseases/irritable-bowel-syndrome/definition-facts
2. Saha, L. (2014). Irritable bowel syndrome: Pathogenesis, diagnosis, treatment, and evidence-based medicine. World Journal of Gastroenterology, 20(22), 6759. https://doi.org/10.3748/wjg.v20.i22.6759
3. Greenan, S. (2021, November 5). A Functional Medicine Approach to IBS. Rupa Health. Retrieved December 6, 2022, from https://www.rupahealth.com/post/a-functional-medicine-approach-to-ibs
4. Wilkins, T., Pepitone, C., Biju, A., et al. (2012). Diagnosis and management of IBS in adults. American Family Physician, 86(5), 419–426.
5. Lacy, B.E., Pimentel, M., Brenner, D.M., et al. (2021). ACG Clinical Guideline: Management of Irritable Bowel Syndrome. American Journal of Gastroenterology, 116(1), 17–44. https://doi.org/10.14309/ajg.0000000000001036
6. Ford, A.C., Quigley, E.M.M., Lacy, B.E., et al. (2014). Efficacy of Prebiotics, Probiotics, and Synbiotics in Irritable Bowel Syndrome and Chronic Idiopathic Constipation: Systematic Review and Meta-analysis. American Journal of Gastroenterology, 109(10), 1547–1561. https://doi.org/10.1038/ajg.2014.202
7. Hemarajata, P., & Versalovic, J. (2012). Effects of probiotics on gut microbiota: mechanisms of intestinal immunomodulation and neuromodulation. Therapeutic Advances in Gastroenterology, 6(1), 39–51. https://doi.org/10.1177/1756283x12459294
8. Gu, Y., Wang, C., Qin, X., et al. (2022). Saccharomyces boulardii, a yeast probiotic, inhibits gut motility through upregulating intestinal serotonin transporter and modulating gut microbiota. Pharmacological Research, 181, 106291. https://doi.org/10.1016/j.phrs.2022.106291
9. Greenan, S. (2021, November 2). A Functional Medicine Approach to SIBO. Rupa Health. Retrieved December 7, 2022, from https://www.rupahealth.com/post/a-functional-medicine-approach-to-sibo