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Hemorrhoids

Last updated: February 28, 2024

Summarytoggle arrow icon

Hemorrhoids are dilated submucosal vascular cushions within the anal canal that can be asymptomatic or manifest as painless perianal masses, pruritus, or intermittent scant hematochezia (bright red blood per rectum, typically at the end of defecation). Excessive straining during defecation or intraabdominal pressure (e.g., due to constipation, pregnancy, or prolonged periods sitting) increase the likelihood of developing hemorrhoids. Based on their anatomical location, hemorrhoids are internal (above the dentate line), external (below the dentate line), or mixed. Internal hemorrhoids are classified into four grades according to the extent of prolapse. The diagnosis is primarily clinical, based on a thorough history and examination that includes a digital rectal examination and anoscopy. Further investigation with proctoscopy, sigmoidoscopy, or colonoscopy may be required to rule out differential diagnoses of hemorrhoids, including colorectal cancer. All patients with symptomatic hemorrhoids should be counseled on lifestyle modifications (e.g., increased fiber and fluid intake, regular physical activity) to reduce straining during defecation. Medical management also includes stool softeners and short-term use of topical medications (e.g., anesthetics, corticosteroids, or vasoconstrictors) for symptomatic relief. Hemorrhoids refractory to medical management and larger (grades III and IV) internal hemorrhoids typically require procedures such as rubber band ligation, sclerotherapy, and infrared coagulation, or surgery. Thrombosed external hemorrhoids manifest with acute pain and a tender bluish-purple perianal nodule. Surgical excision of the thrombosed hemorrhoid may be beneficial in patients who present within 3–4 days of symptom onset. Those who present later should be managed conservatively.

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Etiologytoggle arrow icon

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Pathophysiologytoggle arrow icon

Anatomy of the anal canal

Characteristics of the anal canal above and below the dentate line [3][4]
Above the dentate line Below the dentate line
Embryological origin
Epithelium

Arterial supply

Venous drainage
Lymphatic drainage
Innervation
Clinical relevance

Internal vs. external hemorrhoids

Hemorrhoids are classified as internal , external , or mixed .

Hemorrhoids are not varicose veins (dilated, tortuous veins). Anorectal varices occur, e.g., as a result of portal hypertension. The terms anorectal varices and hemorrhoids are often used interchangeably, but this is incorrect.

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Clinical featurestoggle arrow icon

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Classificationtoggle arrow icon

Internal hemorrhoids are graded according to extent of prolapse. There is no widely used classification system for external hemorrhoids.

Grading of internal hemorrhoids [5]
Grade Palpation findings
I Hemorrhoids bleed but do not prolapse.
II Prolapse when straining, but spontaneously reduce at rest
III Prolapse when straining; only reducible manually
IV Irreducible prolapse; may be strangulated and thrombosed with possible ulceration

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Diagnosistoggle arrow icon

Approach [5][6][7]

Hemorrhoids are a clinical diagnosis.

Physical examination [5][7][8]

Anoscopy [6][8]

  • Insertion of an anoscope to directly visualize the anus and distal rectum [9]
  • Perform in all patients with suspected hemorrhoids. [7][8]
  • May show hemorrhoids or differential diagnoses, e.g., anal carcinoma or fissure

Further studies [6][8][10]

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Differential diagnosestoggle arrow icon

Always consider the possibility of concurrent colorectal carcinoma.

The differential diagnoses listed here are not exhaustive.

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Treatmenttoggle arrow icon

Approach [5][6][7]

Hemorrhoids should only be treated in symptomatic patients. [6]

Medical management of hemorrhoids [5][6][7]

Conservative management is often the only intervention required for grade I–II internal hemorrhoids and external hemorrhoids.

Long-term use of topical medications for hemorrhoids can lead to sensitization and localized reactions and should be avoided. [6]

Office-based procedures for hemorrhoids [5][6][8]

Sclerotherapy may be preferable in patients with actively bleeding hemorrhoids who are on anticoagulants. [5]

Surgery for hemorrhoids [6][7]

Pain is common after surgical treatment of hemorrhoids. Consider multimodal analgesia including local anesthesia and use of topical medications (e.g., diltiazem or nitroglycerin ointment) to reduce the need for opioid analgesics. [6]

Perianal sepsis can occur after surgical or office-based interventions for hemorrhoids and may manifest with worsening pain, fever, or dysuria. [6]

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Thrombosed external hemorrhoidtoggle arrow icon

Definition

A thrombus within the inferior hemorrhoidal venous plexus distal to the dentate line

Pathophysiology

External hemorrhoids are located distal to the dentate (pectinate) line and are drained by the inferior hemorrhoidal (rectal) plexus. External hemorrhoid thrombosis occurs if a clot forms in the inferior hemorrhoidal plexus. [15]

Clinical features [6][8][16]

  • Acute onset of severe perianal pain
  • Painful perianal mass that may ulcerate and bleed
  • Painful defecation

Diagnostics [6]

Management [5][6][8]

Surgical excision [12]

Medical management [6][8]

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Excision of thrombosed external hemorrhoidstoggle arrow icon

Surgical excision may be considered for patients presenting with acute (< 3–4 days), severely painful thrombosed external hemorrhoids. [8]

Contraindications (relative) [17][18]

Equipment checklist

Procedure [17]

  1. Obtain informed consent.
  2. Position the patient in prone or lateral decubitus position.
  3. Retract the buttocks to expose the anal opening.
  4. Prep the skin with an antiseptic solution.
  5. Administer local anesthetic containing epinephrine.
  6. Use forceps to grasp the skin overlying the thrombus.
  7. Make an elliptical incision around the thrombus.
  8. Excise the skin island using the scalpel or dissecting scissors.
  9. Remove the entire thrombus.
  10. Confirm hemostasis.
  11. Apply a gauze dressing.

Use direct pressure, chemical cautery, electrocautery, or a figure-of-eight suture over the bleeding site to control localized bleeding.

Postprocedure checklist [18][19]

Complications

  • Bleeding
  • Infection
  • Recurrence [20]

Incision and drainage of a thrombosed external hemorrhoid is more likely to result in local recurrence; excision is the recommended surgical technique. [6][12]

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Special patient groupstoggle arrow icon

Hemorrhoids in pregnancy [15][21][22]

  • Hemorrhoids are common in pregnant individuals.
  • Management is typically conservative. [23]

Conservative management

Interventions

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