Definition and Overview

Rectal bleeding, medically known as hematochezia when bright red or melena when dark and tarry, refers to the passage of blood from the rectum. The blood may be visible on toilet paper, coating the stool, mixed within the stool, or present in the toilet water. The appearance and characteristics of the blood provide important clues about its source and severity.

The color of blood can indicate where in the digestive tract the bleeding originates. Bright red blood typically comes from the lower digestive tract (rectum, anus, or lower colon), while dark, tarry stools suggest bleeding from higher up in the digestive system. The amount of bleeding can vary from a few drops to significant blood loss requiring emergency treatment.

While rectal bleeding is often caused by benign conditions like hemorrhoids or anal fissures, it can also be a sign of serious conditions including colorectal cancer, inflammatory bowel disease, or gastrointestinal bleeding. Any rectal bleeding warrants medical evaluation to determine the cause and appropriate treatment, especially in people over 50 or those with risk factors for colorectal cancer.

Common Causes

Anorectal Causes

  • Hemorrhoids: Most common cause
  • Anal fissures: Tears in anal lining
  • Anal fistula: Abnormal tract
  • Proctitis: Rectal inflammation
  • Rectal disorders: Various conditions
  • Rectal prolapse: Rectum protrudes
  • Anal cancer: Rare but serious
  • Trauma: From injury or procedures

Colonic Causes

Other Causes

  • GI hemorrhage: Upper GI bleeding
  • Angiodysplasia: Abnormal blood vessels
  • Constipation: Straining effects
  • Gastroenteritis: Inflammation
  • Blood clotting disorders: Bleeding tendency
  • Medications: Blood thinners, NSAIDs
  • Iron deficiency: From chronic bleeding
  • Meckel's diverticulum: In children

Bleeding Characteristics and Associated Symptoms

Types of Bleeding

  • Bright red blood on paper
  • Blood dripping into toilet
  • Blood mixed with stool
  • Blood coating stool surface
  • Dark, tarry stools (melena)
  • Maroon-colored stools
  • Occult blood (hidden)
  • Clots or tissue pieces

Associated Symptoms

When to Seek Emergency Care

Seek immediate medical attention for:

  • Heavy bleeding or blood clots
  • Dizziness, weakness, or fainting
  • Rapid pulse or low blood pressure
  • Severe abdominal pain
  • Vomiting blood
  • Black, tarry stools
  • Confusion or altered mental state
  • Pale skin, cold sweats
  • Bleeding that won't stop
  • Signs of shock

Important: Any rectal bleeding in people over 50 or with family history of colorectal cancer requires prompt evaluation.

Diagnostic Approach

Healthcare providers evaluate rectal bleeding through:

Diagnostic Tests

  • Digital rectal exam: Physical examination
  • Anoscopy: Examine anal canal
  • Sigmoidoscopy: Lower colon viewing
  • Colonoscopy: Full colon examination
  • Blood tests: CBC, clotting studies
  • Stool tests: Occult blood, infection
  • CT scan: For complications
  • Angiography: For active bleeding

Treatment and Management

Conservative Treatment

  • Sitz baths for hemorrhoids
  • High-fiber diet
  • Stool softeners
  • Topical treatments
  • Avoid straining
  • Increase water intake
  • Over-the-counter remedies
  • Rest and monitoring

Medical Interventions

  • Hemorrhoid procedures
  • Fissure treatments
  • Polyp removal
  • Cancer treatment
  • IBD medications
  • Endoscopic therapies
  • Surgery if needed
  • Blood transfusion for severe cases

Prevention

Reduce your risk of rectal bleeding:

  • High-fiber diet: Prevents constipation
  • Stay hydrated: 8+ glasses daily
  • Regular exercise: Promotes bowel health
  • Don't strain: During bowel movements
  • Prompt bathroom visits: Don't delay
  • Healthy weight: Reduces pressure
  • Limit alcohol: Can irritate GI tract
  • Colorectal screening: As recommended
  • Manage chronic conditions: IBD, etc.
  • Safe lifting: Avoid hemorrhoid pressure