The disease may begin gradually or suddenly and typically follows a relapsing-remitting course, with periods of symptom flare-ups alternating with remission. The primary goal of treatment is long-term remission.

Ulcerative colitis most commonly develops between ages 15 and 30 but can occur at any age.

Who Is at Higher Risk

Ulcerative colitis is more likely in people who:

• Have a first-degree relative with IBD

  
  

• Are of Jewish descent

Symptoms

Symptoms vary widely in type and severity and may include:

• Diarrhea

  
  

• Rectal bleeding or blood in the stool

  
  

• Abdominal cramping or pain

  
  

• Urgency or frequent bowel movements

  
  

• Tenesmus (feeling the need to pass stool despite an empty bowel)

  
  

• Passing mucus or pus in stool

  
  

• Fatigue, fever, nausea, vomiting, or weight loss in more severe disease

Mild disease may involve fewer than four bowel movements per day, while severe or fulminant disease may cause more than ten bloody bowel movements daily.

Periods of remission can last weeks to years, followed by symptom relapse.

Causes

The exact cause of ulcerative colitis is unknown. Factors believed to contribute include:

• Genetics: A family history increases risk

  
  

• Immune system dysfunction: Abnormal immune responses cause intestinal inflammation

  
  

• Gut microbiome changes: Differences in intestinal bacteria may play a role

  
  

• Environmental factors: External triggers may influence disease development

Complications

Long-standing or severe ulcerative colitis can lead to complications, including:

• Anemia: From chronic blood loss or inflammation

  
  

• Bone loss: Osteopenia or osteoporosis due to disease or steroid use

  
  

• Growth and developmental delays in children

  
  

• Colorectal cancer: Risk increases with longer disease duration, greater colon involvement, younger age at diagnosis, and coexisting primary sclerosing cholangitis

Serious, Life-Threatening Complications

These require urgent medical care and may include:

• Fulminant ulcerative colitis

  
  

• Severe rectal bleeding

  
  

• Toxic megacolon

  
  

• Perforation of the colon

  
  

• Severe anemia or dehydration

Ulcerative colitis may also affect other parts of the body, including the joints, skin, eyes, liver, and bile ducts. Patients also have an increased risk of blood clots.

Colorectal Cancer Screening

Because ulcerative colitis increases colorectal cancer risk, regular colonoscopy screening is recommended:

• Every 1–3 years starting 8 years after diagnosis

  
  

• Annually starting at diagnosis for patients with primary sclerosing

  cholangitis

Early detection improves outcomes.

Diagnosis

Diagnosis is based on:

• Medical and family history

  
  

• Physical examination (including rectal exam)

  
  

• Diagnostic testing to confirm disease, assess severity, and rule out other conditions

Common tests include:

• Blood tests (to check for inflammation, anemia, infection)

  
  

• Stool tests (to exclude infection and assess inflammation)

• Endoscopy with biopsy:

  
  

  • Colonoscopy (entire colon)

    
    

  • Flexible sigmoidoscopy (rectum and lower colon)

Treatment

Treatment depends on disease severity and extent and aims to control inflammation and maintain remission.

Treatment options include:

• Anti-inflammatory medications (e.g., aminosalicylates)

  
  

• Immune-modulating drugs

  
  

• Biologic therapies

  
  

• Corticosteroids for short-term flare control

Severe or fulminant disease is often treated in the hospital.

Surgery

Surgery may be recommended for:

• Colorectal cancer or precancerous changes

  
  

• Life-threatening complications

  
  

• Symptoms unresponsive to medication

  
  

• Steroid-dependent disease

Surgical options typically involve removal of the colon and rectum, with either:

• An ileoanal pouch (internal reservoir)

  
  

• An ileostomy (external stoma and pouch)

Managing Symptoms and Complications

• Acetaminophen is preferred for pain; NSAIDs should be avoided

  
  

• Calcium and vitamin D may be recommended to protect bone health

  
  

• Severe complications may require IV fluids, blood transfusions, antibiotics, or surgery

Eating, Diet, and Nutrition

There is no single diet proven to cause or cure ulcerative colitis, but maintaining balanced nutrition is important.

General recommendations include:

• Eating a healthy, well-balanced diet

  
  

• Staying hydrated

  
  

• Identifying and avoiding personal trigger foods

  
  

• Adjusting fiber intake during flare-ups

  
  

• Using supplements if recommended

Children and others with reduced intake may need closer nutritional monitoring. A dietitian can help tailor dietary choices.

Important Reminder: This information is intended only to provide general guidance. It does not provide definitive medical advice. It is very important that you consult your doctor about your specific condition.

https://www.niddk.nih.gov/health-information/digestive-diseases/ulcerative-colitis/all-content

[3] Rubin DT, Ananthakrishnan AN, Siegel CA, Sauer BG, Long MD. ACG clinical guideline: ulcerative colitis in adults American Journal of Gastroenterology. 2019;114(3):384–413. doi:10.14309/ajg.0000000000000152

[4] Hanauer SB, Podolsky DK. Chapter 71: Ulcerative colitis. In: Podolsky DK, Camilleri M, Fitz G, et al, eds. Yamada’s Textbook of Gastroenterology. 6th ed. John Wiley & Sons, Ltd; 2016:1378–1417.