External hemorrhoid


Anatomy of the anus.
Internal and external hemorrhoids divided by pectinate (dentate) line
  • Pathologic state cccurs when internal or external hemorrhoid plexus become engorged, prolapsed, or thrombosed
  • Bleeding is usually limited (surface of stool, on toilet tissue, at end of defecation)
    • Passage of blood clots requires evaluation for colon lesions

Risk Factors

Clinical Features

  • Occur distal to dentate line
  • Can be seen at external inspection
    • More prominent with Valsalva
  • Thrombosed hemorrhoids (bluish-purple discoloration) cause painful defecation
  • Prolapse
    • Requires periodic reduction by the patient

Differential Diagnosis

Anorectal Disorders

Undifferentiated lower gastrointestinal bleeding


Not Thrombosed

  • Usually self-limiting with resolution in 1 week


  • Consider conservative treatment (sitz baths and bulk laxatives) if:
    • Thrombosis has been present >72 hrs
    • Swelling has started to shrink
    • Pain is tolerable
  • Conservative treatment may also include topical 0.3% nifedipine and 1.5% viscous lidocaine[1]
  • Consider Perianal block for pain relief
  • Consider excision if:
    • Patient is not immunocompromised, child, pregnant woman, has portal hypertension, coagulopathic
    • Thrombosis is acute (<72 hrs)
    • Extremely painful
    • See External Hemorrhoid Excision


  • Discharge home if uncomplicated
  • Colorectal surgery follow up

See Also

External Links


  1. Perrotti P. Conservative treatment of acute thrombosed external hemorrhoids with topical nifedipine. Dis Colon Rectum. 2001 Mar;44(3):405-9.