Crohn’s disease is a chronic inflammatory bowel disease (IBD) that causes inflammation in the digestive tract. It can affect any part of the digestive tract from the mouth to the anus, but it commonly affects the small intestine and the beginning of the large intestine. Symptoms may come and go, with periods of active disease called flares and periods of remission.
Symptoms
Symptoms vary depending on where the inflammation occurs and how severe it is. Common symptoms include diarrhea, abdominal pain or cramping, weight loss, reduced appetite and fatigue. Some people may have anemia, fever, mouth sores or problems around the anus. Children may have slowed growth or delayed development.
Possible complications
Crohn’s disease can sometimes cause narrowing of the intestine, bowel obstruction, fistulas, abscesses, anal fissures or nutritional deficiencies. Inflammation can also affect the joints, skin, eyes, liver and other parts of the body.
Diagnosis
There is no single test for Crohn’s disease. Assessment may include medical and family history, physical examination, blood tests, stool tests, endoscopy or colonoscopy with biopsies, and imaging of the digestive tract. Testing also helps rule out infections and other conditions that can cause similar symptoms.
Treatment
Treatment aims to reduce intestinal inflammation, control symptoms, heal affected tissue when possible and maintain remission. Medicines may include corticosteroids for selected flares, immunomodulators, biologic medicines or other targeted therapies. Treatment is individualized according to disease location, severity, complications and previous response.
Surgery may be needed for complications such as obstruction, abscesses or fistulas, or when symptoms cannot be adequately controlled with medicines. Surgery can treat damaged areas but does not cure Crohn’s disease, and inflammation can return elsewhere.
Food and nutrition
No single diet is appropriate for everyone with Crohn’s disease. A balanced diet is important, but active inflammation may reduce appetite or nutrient absorption. A healthcare professional or registered dietitian may recommend individual dietary changes or supplements when deficiencies are identified. Smoking can worsen Crohn’s disease and should be avoided.
When to seek medical care
Arrange medical assessment for persistent diarrhea, recurring abdominal pain, blood in the stool, unexplained weight loss, fever or ongoing fatigue. People already diagnosed with Crohn’s disease should contact their healthcare team if symptoms worsen or treatment stops working.
Urgent warning signs
Seek urgent medical care for severe or rapidly worsening abdominal pain, repeated vomiting, a markedly swollen abdomen, inability to pass stool or gas, heavy rectal bleeding, fainting, severe dehydration or signs of serious infection.
Related topics
Sources
Last reviewed: 4 September 2026.
Medical disclaimer: This information is general and does not replace individual medical assessment, diagnosis or treatment.