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.
- Excessive straining; (e.g., from chronic constipation, frequent bowel movements, chronic cough, heavy lifting, benign prostatic hyperplasia)
- Extended periods of sitting (e.g., due to occupation or sedentary lifestyle)
- Older age
- Connective tissue disorder (e.g., Ehlers‑Danlos syndrome, scleroderma)
Anatomy of the anal canal
- Areas of thickened anal mucosa that consist of arteriovenous blood vessels (corpus cavernosum recti), smooth muscle (e.g., Treitz muscle), and fibroelastic tissue (e.g., collagen, elastic fibers)
- Located at 11, 7 and 3 o'clock in the lithotomy position (right anterior, right posterior, and left lateral position)
- Play an important role in maintaining continence by enabling tight closure of the rectum
- Defecation causes contraction of supportive structures (e.g., Treitz muscle) → compression of anal cushions → increased diameter of the anal canal for adequate passage of stool
- Anal columns: longitudinal folds of mucous membrane that are fused at their inferior ends by transverse folds (anal valves)
- Anal sinuses: small, mucus-secreting pouches between the anal columns above the anal valves
- Circular separation line formed by the fusion of anal valves (hindgut-proctodeum junction)
- Divides anal canal into an upper and lower part (also see characteristics of the anal canal above and below the dentate line below)
External anal sphincter
- Composed of
- Subcutaneous external sphincter: surrounds lower third of anal canal
- Superficial external sphincter
- Deep external sphincter
- Consists of skeletal muscle and functions to open and close the anal canal and opening
- Innervated by the pudendal nerve and under voluntary control
- Composed of
Internal anal sphincter
- Surrounds upper two-thirds of anal canal
- Consists of involuntary circular smooth muscle and is responsible for ∼ 85% of the resting pressure of the anal canal
- Innervated by the enteric nervous system
Internal vs. external hemorrhoids
Hemorrhoids are classified as internal , external , or mixed .
- Prolapse of internal hemorrhoids, with possible incarceration and strangulation, may cause pain by triggering an anal sphincter complex spasm. → possible ischemia and necrosis of internal hemorrhoids → worsening anal sphincter complex spasm → potential external hemorrhoid thrombosis → cutaneous pain
- Develop above the dentate line, which is not innervated by cutaneous nerves; distension does not cause pain.
- Bleeding and/or prolapsed internal hemorrhoids irritate sensitive perianal skin → perianal itching
- Develop below the dentate line, which is innervated by cutaneous nerves; distention; of this innervated skin due to thrombosis results in severe pain.
- Acute thrombosis triggers cutaneous pain, lasting 7–14 days → thrombosis resolves → residual skin or skin tags of distended anal skin
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.
- Often painless, bright red bleeding at the end of defecation
- Perianal mass in the event of prolapse
- Anal discharge (containing mucus or fecal debris)
- Ulceration (in hemorrhoid stage IV)
- Manifestations are similar to those of internal hemorrhoids (i.e., bright red bleeding, pruritus, perianal mass)
- A thrombosed external hemorrhoid manifests with severe perianal pain and a tender perianal mass.
Internal hemorrhoids are graded according to extent of prolapse. There is no widely used classification system for external hemorrhoids.
|Grading of internal hemorrhoids |
|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|
- All patients with suspected hemorrhoids: Perform a perianal examination, digital rectal examination, and anoscopy.
- Inconclusive initial evaluation: Refer for proctoscopy or flexible sigmoidoscopy to evaluate the rectum and distal colon.
- Concern for malignancy (age ≥ 50 years , risk factors for colorectal cancer, red flags for colorectal cancer): Colonoscopy (alternatively, CT colonography) is required to evaluate the entire colon. 
Hemorrhoids are a clinical diagnosis.
Physical examination 
- Evaluate in the prone jackknife position, lateral decubitus position, or lithotomy position. 
- Inspect the perianal area for external hemorrhoids and nonreduced internal hemorrhoids.
- Perform a digital rectal examination to evaluate for masses or tenderness.
- Ask the patient to perform the Valsalva maneuver in order to assess for any prolapse of grade II or III hemorrhoids or rectal mucosa.
- Rule out other potential sources of bright red blood per rectum or perianal masses (see “Differential diagnoses of hemorrhoids”).
- Insertion of an anoscope to directly visualize the anus and distal rectum 
- Perform in all patients with suspected hemorrhoids. 
- May show hemorrhoids or differential diagnoses, e.g., anal carcinoma or fissure
Further studies 
- Clinical uncertainty
- Inadequate visualization on anoscopy
- Concern for malignancy
- High risk for malignancy : colonoscopy to visualize the entire colon; see “Initial workup” in “Approach to suspected colorectal cancer” for further information
- Low risk for malignancy : proctoscopy or flexible sigmoidoscopy
- Anal skin tags: benign, painless folds of skin at the anal verge that are residues of previous episodes of inflammation or thrombosed hemorrhoids 
- Hypertrophied anal papillae
- Anal and colorectal carcinoma
- Anal fissures (cause painful bright red bleeding per rectum)
- Anorectal varices
- Condyloma acuminata
- Inflammatory bowel disease (often associated with anal fistulas and abscesses)
- Rectal prolapse
- Perianal dermatitis
Always consider the possibility of concurrent colorectal carcinoma.
The differential diagnoses listed here are not exhaustive.
- All patients with symptomatic hemorrhoids
- Lifestyle modifications to reduce straining during defecation
- Sitz baths and topical medications for short-term symptomatic relief
- Grade I–III internal hemorrhoids unresponsive to conservative treatment: Refer for office-based procedures (e.g., rubber band ligation).
- Grade IV internal hemorrhoids and those unresponsive to other therapies: Refer for surgery (e.g., hemorrhoidectomy, stapled hemorrhoidopexy).
- Symptomatic external hemorrhoids refractory to conservative management: Refer for surgery.
Thrombosed external hemorrhoids
- Presentation within 3–4 days of symptom onset: Consider excision of the thrombosed hemorrhoid.
- Delayed presentation: conservative management
Hemorrhoids should only be treated in symptomatic patients. 
Medical management of hemorrhoids 
- Indications: all patients with hemorrhoids
Interventions to reduce anorectal pressure and straining
Lifestyle modifications 
- High fiber diet (20–30 g/day)
- Increased fluid intake
- Avoidance of fatty foods
- Regular physical activity
- Avoidance of excessive straining 
- Limiting the amount of time spent on the toilet
- Treatment of constipation with short-term (up to 1 week) use of stool softeners (e.g., docusate) or laxatives (e.g., polyethylene glycol 3350) as needed. 
- Lifestyle modifications 
Interventions to alleviate symptoms (e.g., pain, pruritus)
- Sitz baths: a bath in which the buttocks are immersed in warm water for short periods of time
- Topical medications for short-term symptomatic relief: topical anesthetics (e.g., lidocaine), corticosteroids (e.g., hydrocortisone), and/or vasoconstrictors (e.g., phenylephrine)
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. 
Office-based procedures for hemorrhoids 
- Indications: grade I–III internal hemorrhoids with symptoms refractory to medical management 
Rubber band ligation: most common 
- A rubber band at the base of an internal hemorrhoid under vision through an anoscope
- Ligation leads to ischemic necrosis with subsequent fibrosis.
- Sclerotherapy: low risk of bleeding; consider for patients on anticoagulants 
- Infrared coagulation: application of infrared light waves to the base of the hemorrhoid under vision to induce necrosis and scar formation; typically performed for grade I–II internal hemorrhoids 
- Rubber band ligation: most common 
- Potential complications: uncommon; can include bleeding, pain, or infection (including perianal sepsis) 
Sclerotherapy may be preferable in patients with actively bleeding hemorrhoids who are on anticoagulants. 
Surgery for hemorrhoids 
- Symptomatic grade III and IV internal hemorrhoids
- Symptomatic external hemorrhoids or combined external and internal hemorrhoids with prolapse
- No improvement after; , or inability to tolerate, medical and office-based interventions
Submucosal hemorrhoidectomy: surgical removal of hemorrhoids 
- Ferguson approach (closed approach): The mucosal defect is closed (healing by primary intention) after excision of the hemorrhoid. 
- Milligan‑Morgan approach (open approach): The mucosal defect is kept open (healing by secondary intention) after excision of the hemorrhoid.
Stapled hemorrhoidopexy (Longo procedure) 
- A circular stapling device is used to remove a circular wedge of mucosal tissue above the dentate line
- Only effective for internal hemorrhoids
- Doppler-guided hemorrhoidal arterial ligation: identification and ligation of the arteries supplying hemorrhoids
- Submucosal hemorrhoidectomy: surgical removal of hemorrhoids 
- Potential complications: pain, bleeding, acute urinary retention, and rarely, anal stricture/stenosis
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. 
Perianal sepsis can occur after surgical or office-based interventions for hemorrhoids and may manifest with worsening pain, fever, or dysuria. 
Thrombosed external hemorrhoid
A thrombus within the inferior hemorrhoidal venous plexus distal to the dentate line
- Stasis of blood within the external hemorrhoid → thrombus formation → inflammation and distention of the overlying perianal skin → severe pain
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. 
Clinical features 
- Acute onset of severe perianal pain
- Painful perianal mass that may ulcerate and bleed
- Painful defecation
- Typically a clinical diagnosis
- Perianal examination: a palpable, tender, dark red to purplish nodule at the anal verge or just within the anal canal
Surgical excision 
- Indication: severe, acute perianal pain (< 3–4 days duration) 
- Procedure: : See “Excision of thrombosed external hemorrhoids.”
Medical management 
- Patients who present after > 3–4 days of symptom onset
- An alternative to surgery in patients with mild or moderate symptoms who present early
- Analgesia: warm sitz baths , antispasmodic agents (e.g., topical nitroglycerin or nifedipine) , analgesic creams (e.g., lidocaine)
- Topical antiinflammatories: e.g., hydrocortisone cream
- Improve passage of stool: stool softeners (e.g., docusate), increased intake of fluids and fiber
Excision of thrombosed external hemorrhoids
Surgical excision may be considered for patients presenting with acute (< 3–4 days), severely painful thrombosed external hemorrhoids. 
Contraindications (relative) 
- Serious systemic illnesses
- Hemodynamic instability
- Concurrent anorectal disease
- Wide adhesive tape
- Antiseptic solution
- Local anesthetic containing epinephrine (e.g., 1% lidocaine with epinephrine)
- Syringe with 25-gauge needle
- Scalpel (e.g., No. 15 blade, No. 11 blade)
- Small dissecting scissors
- Small grasping forceps
- 4 x 4 gauze squares
- Position the patient in prone or lateral decubitus position.
- Retract the buttocks to expose the anal opening.
- Prep the skin with an antiseptic solution.
- Administer local anesthetic containing epinephrine.
- Use forceps to grasp the skin overlying the thrombus.
- Make an elliptical incision around the thrombus.
- Excise the skin island using the scalpel or dissecting scissors.
- Remove the entire thrombus.
- Confirm hemostasis.
- 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 
- Medical management of hemorrhoids reinforced to the patient
- Wound care discussed
- Return precautions discussed
- Colorectal surgery follow-up, 6 weeks postprocedure
- Recurrence 
Incision and drainage of a thrombosed external hemorrhoid is more likely to result in local recurrence; excision is the recommended surgical technique. 
Special patient groups
Hemorrhoids in pregnancy 
- Hemorrhoids are common in pregnant individuals.
- Management is typically conservative. 
- Provide medical management of hemorrhoids, including treatment of constipation. 
- Advise patients to:
- Perform Kegel exercises to improve muscle tone. 
- Lie on the left side to improve blood flow. 
- When possible, defer office-based procedures for hemorrhoids and surgery for hemorrhoids until after the postpartum period. 
- Consider excision of thrombosed external hemorrhoids for acute thrombosis.