Crohn’s Disease Symptoms: Early Signs, Flare Patterns, and When to See a Doctor

The most common Crohn’s disease symptoms are chronic diarrhea, crampy abdominal pain (often in the lower right abdomen), unexplained weight loss, and fatigue that rest does not fix. Many people also have low-grade fever, mouth ulcers, or problems around the anus, and up to 40% of people with inflammatory bowel disease develop symptoms in the joints, skin, eyes or mouth, according to the Swiss IBD cohort study (Vavricka et al., 2011) [9].

Crohn’s disease (CD) is a chronic form of inflammatory bowel disease (IBD) that can affect any part of the digestive tract, most often the end of the small intestine (the terminal ileum). Symptoms usually build slowly, come and go in flares, and are easy to mistake for irritable bowel syndrome (IBS) or a food intolerance. Diarrhea that wakes you at night, blood in the stool, weight loss you did not try for, or symptoms lasting more than 4 to 6 weeks are the signals to have checked by a gastroenterologist.

What Are the Symptoms of Crohn’s Disease?

Crohn’s disease symptoms fall into three groups: gut symptoms, whole-body symptoms caused by inflammation, and symptoms outside the gut. The gut symptoms are chronic diarrhea, abdominal pain and cramping, urgency, and sometimes blood or mucus in the stool. The whole-body symptoms are fatigue, low-grade fever, reduced appetite and weight loss.

Symptoms outside the gut, called extraintestinal manifestations, include joint pain, red tender bumps on the shins, red or painful eyes, and mouth ulcers. Problems around the anus, such as skin tags, fissures, abscesses and fistulas, are a distinctive Crohn’s feature that IBS does not cause. The table below lists each symptom with the figure and source cited for it further down.

Early Warning Signs of Crohn’s Disease

Crohn’s disease often develops gradually. The average delay between symptom onset and diagnosis is 6-9 months, but some patients go years before receiving a correct diagnosis [1]. This delay matters because early treatment reduces the risk of complications and may alter the disease course.

Here are the symptoms that should raise suspicion, especially when they persist for more than 4-6 weeks:

Chronic Diarrhea

Frequent loose stools lasting more than 4 weeks is the most common presenting symptom. Unlike infectious diarrhea, which resolves within days, Crohn’s-related diarrhea is persistent and often waxes and wanes over weeks to months. Stools may contain mucus. Visible blood is possible but less common than in ulcerative colitis, since Crohn’s frequently affects the small bowel rather than the rectum [2].

Nocturnal diarrhea (waking from sleep to have a bowel movement) is a particularly important red flag. IBS virtually never causes nocturnal symptoms, so diarrhea that disrupts sleep points strongly toward an organic cause like IBD.

Abdominal Pain

Pain location often correlates with disease location. Right lower quadrant pain is classic for ileal Crohn’s (the terminal ileum is the most commonly affected site). Pain may be crampy or constant, often worse after eating, and may mimic appendicitis. Periumbilical pain suggests small bowel involvement, while left-sided pain points toward colonic disease [3].

In early disease, pain may be mild and intermittent, easily dismissed as “a sensitive stomach” or stress-related. Persistent pain in the same location, even if mild, warrants investigation if it has lasted several weeks.

Unexplained Weight Loss

Weight loss occurs in 50-70% of Crohn’s patients at diagnosis. The mechanisms are multiple: reduced food intake (eating triggers pain and diarrhea, so patients eat less), malabsorption from inflamed small bowel mucosa, increased metabolic demands from chronic inflammation, and protein loss through damaged intestinal lining [4].

Unintentional weight loss of more than 5% of body weight over 6 months, without a clear explanation, always deserves medical evaluation. In children and teenagers, slowed growth or delayed puberty can be the main sign, because inflammation and poor absorption hold back height gain before weight loss becomes obvious.

Fatigue

This is often the most debilitating symptom and the most underestimated. Crohn’s-related fatigue goes beyond normal tiredness. It is a deep, persistent exhaustion that does not resolve with rest. Contributing factors include anemia (from iron or B12 deficiency), chronic inflammation (pro-inflammatory cytokines directly cause fatigue), nutritional deficiency, disrupted sleep from nocturnal symptoms, and the psychological burden of chronic illness [5].

In some patients, fatigue is the first and most prominent symptom, appearing before obvious GI complaints develop.

Low-Grade Fever

Intermittent fevers of 99-101°F (37.2-38.3°C) occur in active Crohn’s disease due to systemic inflammation. A persistent low-grade fever without an obvious source, particularly when combined with other symptoms on this list, should prompt evaluation for IBD.

Mouth Ulcers

Aphthous ulcers (canker sores) occur in 20-30% of Crohn’s patients and can precede intestinal symptoms by months or years. While common in the general population, frequent or recurrent aphthous ulcers combined with GI symptoms suggest Crohn’s involvement [6].

Perianal Symptoms

Pain, swelling, itching or discharge around the anus can be an early Crohn’s sign, sometimes years before bowel symptoms. Large or inflamed skin tags, an anal fissure that will not heal, or a recurring abscess near the anus are features of Crohn’s disease that IBS and hemorrhoids alone do not explain, and they are worth mentioning to your doctor by name.

What Do Mild Crohn’s Symptoms Look Like?

Mild Crohn’s symptoms usually mean a few more loose stools a day than normal, intermittent cramping or a dull ache in the lower right abdomen, tiredness, and little or no weight loss, while you can still eat, drink, work and sleep most nights. Mild disease often flies under the radar because each symptom on its own looks ordinary: a touchy stomach after meals, a run of canker sores, or an afternoon slump.

The American College of Gastroenterology clinical guideline on Crohn’s disease in adults (Lichtenstein et al., 2018) describes mild to moderate disease as an ambulatory patient who can eat and drink without dehydration, high fever, rigors, abdominal tenderness, a painful abdominal mass, bowel obstruction, or weight loss of more than 10% [16]. Any of those features moves the picture into moderate to severe disease.

How Doctors Grade Crohn’s Severity

Gastroenterologists score symptom severity with two standard tools. The Crohn’s Disease Activity Index (CDAI), developed by Best and colleagues for the National Cooperative Crohn’s Disease Study (1976), combines a week of symptom diary entries with exam and lab findings [18]. The Harvey-Bradshaw Index (HBI), published in the Lancet by Harvey and Bradshaw (1980), is a shorter bedside version built from general well-being, abdominal pain, the number of liquid stools in a day, an abdominal mass, and complications [19].

The CDAI cutoffs are the ones used in the ACG guideline [16], and the matching HBI ranges come from Best’s 2006 comparison of the two indexes in Inflammatory Bowel Diseases [20]. Both scores measure how you feel, not how much inflammation is present.

Why Mild Symptoms Still Deserve a Workup

Mild symptoms and mild inflammation are not the same thing. Some people with few symptoms have deep ulcers on colonoscopy, and inflammation that keeps going quietly can turn into scarring, narrowing and fistulas over the years, a progression documented in the long-term French cohort followed by Cosnes and colleagues (2002) [8].

That is why current practice aims beyond symptom relief. The STRIDE-II consensus from the International Organization for the Study of Inflammatory Bowel Diseases (Turner et al., 2021) sets symptom relief as a short-term target and normalized CRP and fecal calprotectin, then endoscopic healing, as the longer-term goals [21]. A fecal calprotectin test is a simple first step if mild symptoms have lasted more than a few weeks.

Crohn’s Symptoms by Location in the Gut

Crohn’s symptoms depend on where the inflammation sits. Doctors record location and behavior with the Montreal classification, set out by Satsangi and colleagues in Gut (2006) [17]. Knowing your disease location explains why your symptoms may look different from someone else’s with the same diagnosis.

The Montreal classification also records disease behavior: B1 is inflammatory only, B2 is stricturing (narrowing), and B3 is penetrating (fistulas or abscesses). Behavior tends to shift from B1 toward B2 or B3 over time, which is the reason ongoing inflammation is treated even when symptoms are mild.

How Crohn’s Symptoms Differ From IBS and Ulcerative Colitis

Crohn’s vs. IBS

This is the most common diagnostic confusion, and the distinction matters enormously. IBS is a functional disorder with no structural damage; Crohn’s is an inflammatory disease that destroys tissue.

Key differentiators:

• Blood in stool: Absent in IBS. Present in many Crohn’s patients (though not all).
• Weight loss: Absent or minimal in IBS. Common in Crohn’s.
• Nocturnal symptoms: Very rare in IBS. Common in Crohn’s.
• Fever: Absent in IBS. Present in active Crohn’s.
• Elevated inflammatory markers: CRP and fecal calprotectin are normal in IBS and elevated in Crohn’s. Fecal calprotectin is particularly useful as a screening test; a level below 50 mcg/g essentially rules out IBD [7].
• Perianal disease: Skin tags, fissures, and fistulas around the anus occur in Crohn’s but not IBS.
• Extraintestinal symptoms: Joint pain, skin lesions, and eye inflammation suggest IBD, not IBS.

Approximately 20-30% of Crohn’s patients were initially diagnosed with IBS. If you have been told you have IBS but your symptoms include any of the red flags listed above, ask your doctor about fecal calprotectin testing.

Crohn’s vs. Ulcerative Colitis

Both are forms of inflammatory bowel disease, but they differ in important ways:

• Location: UC affects only the colon and rectum, in a continuous pattern starting from the rectum. Crohn’s can affect any part of the GI tract from mouth to anus, and involvement is often patchy (“skip lesions”).
• Depth of inflammation: UC affects only the mucosal surface. Crohn’s is transmural, meaning it extends through the full thickness of the bowel wall, which is why it causes fistulas and strictures.
• Rectal bleeding: Almost universal in UC. Less common in Crohn’s, particularly when disease is limited to the small bowel.
• Perianal disease: Common in Crohn’s (up to 30-40%). Rare in UC.
• Small bowel involvement: Absent in UC (by definition). Present in approximately 70% of Crohn’s cases [8].

Extraintestinal Manifestations

Crohn’s disease is a systemic inflammatory condition, not just a bowel disease. Up to 40% of patients develop symptoms outside the GI tract, and in some cases, these are the presenting complaint that leads to diagnosis [9].

Joint Involvement

The most common extraintestinal manifestation. Two patterns occur:

• Peripheral arthropathy: Affects large joints (knees, ankles, wrists, elbows). Tends to flare alongside intestinal disease activity. Non-erosive and non-deforming, unlike rheumatoid arthritis.
• Axial arthropathy: Affects the spine and sacroiliac joints, causing stiffness and pain that is worse in the morning and improves with movement. Can progress independently of intestinal disease activity. Associated with HLA-B27 positivity. Resembles ankylosing spondylitis.

Skin Manifestations

• Erythema nodosum: Tender, raised red nodules, typically on the shins. Occurs in 10-15% of patients and usually correlates with active bowel disease.
• Pyoderma gangrenosum: Painful, rapidly enlarging ulcers, most often on the legs. Less common (1-2%) but more severe. Can occur independently of bowel disease activity and requires aggressive treatment.

Eye Inflammation

• Episcleritis: Redness and mild pain in the whites of the eyes. Usually self-limiting and correlates with bowel flares.
• Uveitis: Inflammation of the uveal tract (iris, ciliary body, choroid). Causes eye pain, redness, light sensitivity, and blurred vision. Requires prompt ophthalmologic treatment to prevent vision damage. Occurs in 2-5% of IBD patients [10].

Mouth Ulcers

Aphthous ulcers are the most common oral manifestation. Less frequently, Crohn’s can cause granulomatous inflammation of the lips, gums, or buccal mucosa (oral Crohn’s disease), presenting as swelling, cobblestoning, or deep linear ulcers.

Liver and Biliary Involvement

Primary sclerosing cholangitis (PSC), a chronic inflammatory condition of the bile ducts, is associated with IBD (more commonly UC than Crohn’s). Elevated liver enzymes on routine blood work should prompt evaluation.

Flare Patterns and Triggers

Crohn’s disease follows a relapsing-remitting course. Periods of active inflammation (flares) alternate with periods of relative quiescence (remission). Understanding your personal flare pattern helps with both prevention and early intervention.

Common Flare Triggers

• NSAID use: Ibuprofen, naproxen, and aspirin can trigger or worsen Crohn’s flares by disrupting the intestinal mucosal barrier. This is one of the most well-documented and avoidable triggers [11]. Use acetaminophen for pain relief when possible.
• Antibiotic use: Broad-spectrum antibiotics disrupt the gut microbiome and can precipitate flares. When antibiotics are medically necessary, discuss probiotics and monitoring with your gastroenterologist.
• Smoking: The most modifiable risk factor in Crohn’s disease. Smoking doubles the risk of flares, increases the need for surgery, and worsens post-surgical recurrence rates. Quitting smoking is the single most impactful lifestyle change a Crohn’s patient can make [12].
• Psychological stress: While stress does not cause Crohn’s disease, it can trigger flares through the gut-brain axis. Elevated cortisol alters gut permeability, microbiome composition, and immune function. Stress management is a legitimate part of Crohn’s disease care.
• Dietary indiscretions: High-sugar, ultra-processed, or alcohol-heavy diets are commonly reported flare triggers. See our article on Crohn’s disease diet for evidence-based dietary guidance.
• Infections: Gastroenteritis (stomach bugs) can trigger Crohn’s flares, likely by disrupting the already-compromised mucosal immune system.
• Medication non-adherence: Stopping maintenance medications, even when feeling well, is one of the most common reasons for relapse. Crohn’s is a chronic disease; feeling well on medication does not mean the disease is gone.

Recognizing an Incoming Flare

Many patients learn to recognize early signals that a flare is developing:

• Increased stool frequency or looser consistency
• Return of abdominal pain, even if mild
• Rising fatigue that is disproportionate to activity level
• Loss of appetite or mild nausea
• Low-grade fever
• Joint pain or mouth ulcers appearing

Early intervention (contacting your gastroenterologist, adjusting diet, ensuring medication adherence) at the first sign of a flare can sometimes prevent full-blown disease activity. Do not wait for severe symptoms to develop before reaching out to your care team.

What Do Crohn’s Flare Symptoms Feel Like?

Crohn’s disease flare symptoms are a return or worsening of your usual disease pattern: more frequent and looser stools, cramping that comes back after meals, deeper fatigue, reduced appetite, and sometimes low-grade fever, night sweats, joint aches or new mouth ulcers. People with perianal disease may notice new pain, swelling or drainage near the anus. A flare usually builds over days rather than hours.

Several things can look like a flare without being one. An intestinal infection, including Clostridioides difficile, can mimic active Crohn’s, which is why gastroenterologists often order stool tests before changing treatment. Crampy pain with bloating and vomiting after meals can point to a stricture rather than active inflammation, and some people in remission have IBS-type symptoms on top of Crohn’s. CRP and fecal calprotectin help tell these apart.

How Long Does a Crohn’s Flare Last?

A Crohn’s flare can last from a few days to several weeks or longer, and there is no fixed length. Mild flares sometimes settle once a trigger such as an NSAID or an infection is removed. Most moderate or severe flares need a change in treatment, such as a course of corticosteroids, a dose adjustment, or a switch to a different biologic, before symptoms ease. Track stool frequency, pain and energy daily so your care team can see the trend.

Complications of Crohn’s Disease

Because Crohn’s inflammation extends through the full thickness of the bowel wall, it can cause structural complications that IBS and UC typically do not. Approximately 50% of Crohn’s patients develop at least one complication within 20 years of diagnosis [13].

Strictures

Chronic inflammation leads to fibrosis (scarring), which narrows the bowel lumen. Symptoms include crampy abdominal pain after eating (especially high-fiber or bulky meals), nausea, vomiting, bloating, and eventually signs of bowel obstruction if the narrowing becomes severe. Strictures can sometimes be treated with endoscopic balloon dilation, but many eventually require surgical resection.

Fistulas

Transmural inflammation can create abnormal connections (fistulas) between the bowel and other structures:

• Perianal fistulas: Tunnels between the rectum/anal canal and the skin near the anus. Cause pain, drainage, and recurrent abscess formation. Affect up to 30% of Crohn’s patients.
• Enteroenteric fistulas: Connections between two loops of bowel. May cause malabsorption or bypass of significant bowel segments.
• Enterovesical fistulas: Connections between bowel and bladder. Cause recurrent urinary tract infections and passage of air or stool in urine (pneumaturia, fecaluria).
• Enterocutaneous fistulas: Connections between bowel and skin surface. Cause drainage of intestinal content through the skin.

Abscesses

Walled-off collections of pus that form when transmural inflammation or perforation leads to contained infection. Symptoms include localized pain, fever, elevated white blood cell count, and sometimes a palpable mass. Abscesses usually require drainage (percutaneous or surgical) and antibiotics.

Malnutrition

Chronic malabsorption, reduced intake, and increased metabolic demands create ongoing nutritional risk. Severe protein-calorie malnutrition can develop, particularly during prolonged flares. Micronutrient deficiencies (B12, iron, vitamin D, zinc, folate) are nearly universal without proactive monitoring and supplementation.

When Symptoms Require Urgent Care

Most Crohn’s symptoms can be managed through your gastroenterologist’s office. However, certain presentations require urgent evaluation, either at an emergency department or through same-day contact with your GI team:

• Signs of bowel obstruction: Severe crampy abdominal pain, inability to pass gas or stool, vomiting (especially bilious or feculent), progressive abdominal distension. This is a surgical emergency if complete.
• High fever (>101.3°F / 38.5°C) with abdominal pain: Suggests abscess, perforation, or serious infection, especially in patients on immunosuppressive therapy.
• Heavy rectal bleeding: While some blood with stool is common in Crohn’s, large-volume bleeding (filling the toilet bowl, passing clots, feeling lightheaded) requires emergency evaluation.
• Sudden, severe abdominal pain: Especially if different from your typical flare pattern. Could indicate perforation or acute obstruction.
• Signs of sepsis: High fever, rapid heart rate, confusion, low blood pressure. Patients on biologics or immunosuppressants are at higher infection risk.
• Severe dehydration: Inability to keep fluids down, reduced urine output, dizziness on standing. Dehydration from persistent vomiting or severe diarrhea can escalate quickly.

The Diagnostic Workup

If your symptoms suggest Crohn’s disease, here is what to expect from the diagnostic process:

Blood Tests

Initial labs typically include complete blood count (looking for anemia, elevated white cell count), CRP (C-reactive protein, a marker of systemic inflammation), ESR (erythrocyte sedimentation rate), albumin (low in malnutrition and active inflammation), and a comprehensive metabolic panel. Serological markers like ASCA (anti-Saccharomyces cerevisiae antibodies) and pANCA can help differentiate Crohn’s from UC but are not diagnostic alone [14].

Fecal Calprotectin

A stool test that measures calprotectin, a protein released by neutrophils in the intestinal lining during inflammation. Highly sensitive for detecting intestinal inflammation and useful for distinguishing IBD from IBS. A normal fecal calprotectin (<50 mcg/g) makes IBD very unlikely [7].

Colonoscopy With Biopsies

The gold standard for diagnosis. Colonoscopy allows direct visualization of the colonic and terminal ileal mucosa. Crohn’s-specific findings include skip lesions (patchy inflammation with normal mucosa between affected areas), aphthous ulcers, deep serpiginous ulcers, cobblestone appearance, and strictures. Biopsies showing non-caseating granulomas are highly suggestive of Crohn’s, though they are only found in 30-40% of cases [15].

Cross-Sectional Imaging

MR enterography (MRE) or CT enterography (CTE) are essential for evaluating small bowel disease, which is not reachable by colonoscopy. These imaging studies can detect bowel wall thickening, strictures, fistulas, abscesses, and active inflammation. MRE is preferred in younger patients to avoid radiation exposure from CT.

Capsule Endoscopy

A swallowed video capsule that photographs the small bowel as it passes through. Useful for detecting subtle small bowel mucosal disease missed by cross-sectional imaging. Must be used cautiously in patients with suspected strictures due to capsule retention risk.

Upper Endoscopy

Performed when upper GI Crohn’s is suspected (esophageal, gastric, or duodenal involvement). Less common but important in patients with upper GI symptoms or children being evaluated for growth failure.

Who Treats Crohn’s Disease, and Where Integrative Care Fits

A gastroenterologist diagnoses and leads the treatment of Crohn’s disease, ideally one who focuses on inflammatory bowel disease at an IBD center. The wider team often includes a colorectal surgeon for strictures, fistulas and abscesses, a registered dietitian, and, when symptoms spread beyond the gut, a rheumatologist, dermatologist or ophthalmologist. A primary care physician or pediatrician is usually the first stop and orders the initial blood and stool tests.

Standard medical treatment depends on severity and location. It includes corticosteroids such as budesonide and prednisone for short-term control, immunomodulators such as azathioprine, 6-mercaptopurine and methotrexate, and biologic or small-molecule drugs approved by the US Food and Drug Administration (FDA) for moderate to severe Crohn’s, including infliximab, adalimumab, certolizumab pegol, vedolizumab, ustekinumab, risankizumab and upadacitinib. Exclusive enteral nutrition is a first-line option in children, and surgery remains part of care for complications. The Crohn’s disease condition overview covers the causes and treatment options in more depth, and the complete Crohn’s disease guide walks through long-term management.

Integrative and Regenerative Options People Ask About

Some people with Crohn’s also look at integrative care alongside their gastroenterologist’s plan. Nutrient IV therapy is one example: lab-guided IV iron is standard medical care for iron deficiency anemia in IBD, while wellness vitamin drips are cash pay and have little Crohn’s-specific evidence. Read the IV therapy treatment guide before booking, and if you go ahead, you can compare clinics offering IV therapy in the directory.

Mesenchymal stem cell therapy for Crohn’s, mainly studied for perianal fistulas, is investigational in the United States and is best accessed through trials registered on ClinicalTrials.gov. An adipose-derived stem cell product approved in Europe for complex perianal fistulas lost that approval in 2024 after its confirmatory phase 3 trial missed its main goal. The stem cell therapy guide explains what the evidence does and does not show, and the national list of stem cell therapy providers lets you check credentials before any consultation. Low-dose naltrexone (LDN) is used off label for Crohn’s on limited trial evidence, covered in our post on LDN for Crohn’s disease.

Regenerated.com is free for patients. Listing order in the directory is not paid ranking, Featured slots are labeled and capped, and Verified means a clinic completed credential checks, not that it spent money with us. Inclusion in the directory is not an endorsement, and how Featured, Verified and organic listings differ sets out each label in full. Keep your gastroenterologist informed about any integrative treatment you start.

Frequently Asked Questions About Crohn’s Disease Symptoms

What are usually the first signs of Crohn’s disease?

The first signs of Crohn’s disease are usually diarrhea lasting more than 4 weeks, cramping pain in the lower right abdomen, fatigue, and weight loss you did not plan. Some people first notice recurrent mouth ulcers, a painful skin tag or fissure near the anus, joint aches, or in teenagers, slowed growth. Diarrhea that wakes you at night or comes with blood points toward inflammatory bowel disease rather than IBS and should be checked by a doctor.

What do mild Crohn’s symptoms feel like?

Mild Crohn’s symptoms feel like a few extra loose stools a day, on-and-off cramping after meals, and tiredness, without high fever, dehydration, or major weight loss. The American College of Gastroenterology (2018) describes mild to moderate disease as someone who can eat and drink normally and has no tender abdominal mass, obstruction, or weight loss above 10%. Mild symptoms can still hide active inflammation, so a fecal calprotectin test or colonoscopy is worth doing.

What are the symptoms of a Crohn’s flare?

A Crohn’s flare brings back or worsens your usual symptoms: more frequent loose stools, abdominal pain after meals, fatigue, poor appetite, and sometimes low-grade fever, joint pain, mouth ulcers or new pain and drainage near the anus. Flares usually build over several days. Contact your gastroenterologist early, because infections such as Clostridioides difficile and strictures can look like a flare. Go to urgent care for high fever, vomiting with a swollen belly, or heavy bleeding.

Can you have Crohn’s disease without diarrhea?

Yes, Crohn’s disease can occur without diarrhea, especially when it affects the small intestine or causes narrowing. Some people mainly have abdominal pain, bloating, nausea, fatigue, weight loss or anemia, and people with strictures may even become constipated. Others first show up with perianal abscesses, mouth ulcers, joint pain or slowed growth in childhood. Blood tests, a fecal calprotectin test and imaging such as MR enterography can find inflammation that the bowel pattern hides.

Can blood tests be normal if you have Crohn’s disease?

Yes, routine blood tests can be normal in Crohn’s disease, particularly when inflammation is mild or limited to the small bowel. CRP does not rise in every patient, so a normal result does not exclude Crohn’s. Fecal calprotectin, a stool test, is more sensitive for gut inflammation, and a level below 50 mcg/g makes IBD very unlikely, according to a BMJ meta-analysis (van Rheenen et al., 2010). Colonoscopy with biopsies and cross-sectional imaging confirm the diagnosis.

How can you tell Crohn’s disease from IBS?

Crohn’s disease causes inflammation and tissue damage, while irritable bowel syndrome does not. Night-time diarrhea, blood in the stool, weight loss, fever, anemia, perianal fistulas and raised CRP or fecal calprotectin all point toward Crohn’s rather than IBS. Roughly 20-30% of people with Crohn’s were first told they had IBS. The irritable bowel syndrome condition page covers the IBS side, and celiac disease is another cause doctors rule out.

Related Reading

• Crohn’s Disease Diet: What to Eat, What to Avoid, and Evidence-Based Approaches
• IBS Symptoms: What They Mean and What to Do
• Leaky Gut Symptoms: Separating Fact From Fiction
• IBS vs SIBO: How to Tell the Difference and Why It Matters

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