Anal Fissure



  • Hard stool passes and “cuts” anoderm
  • Linear tear extends from dentate line to anoderm:
    • Posterior midline 95%
    • Anterior midline 5%
    • Externally: Forms skin tag or sentinel pile
    • Internally: Forms hypertrophied anal papilla
    • Chronic fissure may reveal an ulcer with fibers of internal sphincter with sentinel pile


  • Stress or an overly tight anal sphincter leads to local ischemia of posterior anoderm
  • Diarrhea or hard bowel movement tears anoderm
  • Local trauma from anal intercourse or sexual abuse may be the cause
  • Lateral fissures indicate underlying causative systemic disease:
    • Crohn disease
    • Anal cancer
    • Leukemia
    • Syphilis
    • Previous anal surgery


Signs and Symptoms

  • Bright red blood per rectum usually on toilet paper
  • Sharp, cutting, throbbing, or burning pain with bowel movement:
    • May last for hours
  • Constipation; unable to pass stool owing to pain:
    • Hard, nondeformable stools

  • Passage of hard stool or constipation
  • Episode(s) of diarrhea
  • Bright red blood on toilet paper

Physical Exam
Anal exam:
  • Gently retract buttocks and have patient bear down to visualize the fissure
  • Severe pain usually prevents a manual or digital exam:
    • Use lidocaine jelly or ELA-Max5, a topical lidocaine ointment, before attempting digital rectal exam
    • Need to exclude abscess or tumor

Pediatric Considerations
A clear test tube may be used as an anoscope to visualize the anal canal/fissure

Essential Workup

Careful rectal exam

Diagnostic Tests and Interpretation

Hematocrit if severe bleeding by history

CT pelvis:
  • To exclude anal rectal abscess/tumor if palpable mass on rectal exam

Differential Diagnosis

  • Crohn disease
  • Chronic ulcerative colitis
  • Anorectal carcinoma
  • Perirectal abscess
  • Thrombosed hemorrhoid
  • Sexual abuse
  • TB
  • Syphilis
  • Lymphoma
  • Leukemia
  • Previous anal surgery


Pre Hospital

Establish IV access for patients with significant rectal bleeding

Initial Stabilization/Therapy

Administer pain medications for patients with significant pain

Ed Treatment/Procedures

  • IV/IM/PO pain medications:
    • NSAIDs
    • Acetaminophen
    • Muscle relaxants to relieve sphincter spasm:
      • Cyclobenzaprine
      • Diazepam
      • Diltiazem 2% ointment
      • Nifedipine ointment 0.3%
  • Topical anesthetics:
    • ELA-Max5
    • Lidocaine jelly 2%
  • Sitz baths (with warm water) to relieve sphincter spasm

  • High-fiber diet instruction:
    • Fiber/bran: 20 g/d
    • Psyllium seeds (Metamucil or Konsyl): 1–2 tsp (peds: 0.25–1 tsp/d) PO q24h
  • Encourage consumption of 10–12 oz glasses of water per day


  • Cyclobenzaprine (Flexeril): 10 mg (peds: Not indicated) PO TID
  • Diazepam (Valium): 5 mg (peds: 0.12–0.8 mg/kg/d) PO TID PRN for spasm
  • Diltiazem 2% ointment: Apply to fissure BID
  • Docusate sodium (Colace): 50–200 mg (peds: <3 yr, 10–40 mg/d; 3–6 yr, 20–60 mg/d; 6–12 yr, 40–150 mg/d) PO q12h
  • ELA-Max5 (5% lidocaine anorectal cream): Apply to perianal area q4h PRN pain (pediatric dose: Not for those <12 yr)
  • Ibuprofen: 400–600 mg (peds: 40 mg/kg/d) PO q6h
  • Nifedipine ointment 0.3%: Apply to fissure TID with cotton swab (peds: Not indicated)
  • Nitroglycerin ointment 0.2%: Apply a small pea-sized dot to fissure BID–TID with cotton swab. (peds: Not indicated)

Ongoing Care


Admission Criteria
Severe abdominal pain/distention due to fecal impaction

Discharge Criteria
  • Initial treatment is conservative therapy for acute anal fissures as an outpatient
  • Operative referral for chronic fissures

Follow-Up Recommendations

Colorectal or GI follow-up for patients with symptomatic fissures

Pearls and Pitfalls

  • Perform a careful physical exam of rectal area to delineate fissures and exclude other pathology
  • Provide combination of pain relief and muscle relaxants for patients with significant pain
  • Provide discharge medications/instructions to prevent constipation

Additional Reading

  • Herzig DO, Lu KC. Anal fissure. Surg Clinf North Am. 2010;90(1):22–44.
  • Nelson RL, Thomas K, Morgan J, et al. Non-surgical therapy for anal fissure. Cochrane Database Syst Rev. 2012;2:CD003431.
  • Orsay C, Rakinic J. Practice parameters for the management of anal fissures (revised). Dis Colon Rectum. 2004;47:2003–2007.
  • Rakinic J. Anal fissure. Clin Colon Rectal Surg. 2007;20(2):133–138.

See Also


Julia H. Sone

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