An anal fissure is a painful condition associated with a linear tear at the anus secondary to defecation of hard stool or mucosal ischemia.


Clinical features of anal fissure:

(1) linear tear of skin and mucosa crossing the anus

(2) anal pain, especially on defecation

(3) anal sphincter spasm or hypertonia

(4) anal bleeding

(5) complications may include a sentinel skin tag, hypertrophied anal papillae and fibrosis


An acute anal fissure may heal spontaneously. A chronic fissure (one lasting >= 12 weeks according to Scholefield et al, others use > 6 weeks) usually requires some form of treatment before it resolves.


Management of Chronic Anal Fissue


surgical lateral sphincterotomy

fecal incontinence

nitroglycerin ointment (glyceryl trinitrate), 0.1 to 0.4%


diltiazem hydrochloride (Cardiazem) ointment


botulinum toxin injection




• The use of nitroglycerin may be referred to as a “chemical sphincterotomy”.

• Nitroglycerin results in release of nitrous oxide (NO) which relaxes smooth muscle.

• Diltiazem is a calcium channel blocker.


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