Hemorrhoids is a topic covered in the 5-Minute Clinical Consult.

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  • Varicosities of the hemorrhoidal venous plexus
  • External hemorrhoids
    • Located below the dentate line; visceral innervation (painful)
    • Covered by squamous epithelium
  • Internal hemorrhoids
    • Located above the dentate line; somatic innervation (painless)
    • Covered by columnar epithelium
    • Classification of internal hemorrhoids (1):
      • Grade I: Hemorrhoid vessel bulges without prolapse.
      • Grade II: Hemorrhoid prolapses with straining but reduces spontaneously.
      • Grade III: Hemorrhoid prolapses with straining and requires manual reduction.
      • Grade IV: chronically prolapsed—can’t be reduced
  • Internal and external hemorrhoids often coexist.
  • Although often asymptomatic, hemorrhoids can present with itching, bleeding, soilage, prolapse, or pain.
  • Pain and Thrombosis more common with external than internal hemorrhoids.

Geriatric Considerations
Hemorrhoids and rectal prolapse are more common in elderly.

Pediatric Considerations
  • Uncommon in infants and children; most common cause is chronic liver failure; other findings (rectal polyps, skin tags, condyloma) often misdiagnosed as hemorrhoids
  • In adolescents, chronic constipation and prolonged toilet time can result in hemorrhoids.
Pregnancy Considerations
  • Common in pregnancy
  • Usually resolves after delivery
  • No treatment required, unless extremely painful


  • Predominant age: adults; peak from 45 to 65 years (2)
  • Predominant sex: male = female


  • ~4–5% in general population in the United States
  • 39% prevalence on routine screening colonoscopy (2)

Etiology and Pathophysiology

  • Exact pathophysiology is unknown.
  • There are three primary hemorrhoidal cushions—typically located in left lateral, right anterior, and right posterior positions. Hemorrhoidal cushions augment anal closing pressure and protect the anal sphincter during stool passage. During Valsalva, increased intra-abdominal pressure raises pressure within the hemorrhoidal cushions. Mechanisms implicated in symptomatic hemorrhoidal disease include:
    • Dilated veins of hemorrhoidal plexus
    • Tight internal anal sphincter
    • Abnormal distention of the arteriovenous anastomosis
    • Prolapse of the cushions and the surrounding connective tissues

No known genetic pattern

Risk Factors

  • Pregnancy
  • Pelvic space-occupying lesions
  • Liver disease; portal HTN
  • Constipation
  • Occupations that require prolonged sitting
  • Loss of perianal muscle tone due to old age, rectal surgery, birth trauma/episiotomy, anal intercourse
  • Obesity
  • Chronic diarrhea

General Prevention

  • Avoid constipation by consuming high-fiber diet (>30 g/day) and ensuring proper hydration.
  • Maintain appropriate weight.
  • Avoid prolonged sitting or straining on the toilet.

Commonly Associated Conditions

  • Liver disease; cirrhosis, ascites
  • Pregnancy
  • Constipation

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