Anal Fissure is a tear in the lining of the anal canal, which then exposes the underlying muscle of the internal sphincter. Fissures typically occur spontaneously, or as a result of difficult or hard bowel movements. Once the sphincter muscle is exposed it goes into spasm causing discomfort and painful evacuation. In most circumstances the pain is intense. In order to relieve the pain, the internal anal sphincter muscle needs to be relaxed.

Pain Relief

The most common methods employed to treat anal fissures are:

  • Surgical Sphincterotomy – The internal anal sphincter muscle is surgically divided to relax it.
  • Chemical Sphincterotomy – Pharmacological Relaxants are applied intra-anally to relax the internal anal sphincter.

Surgical Sphincterotomy

Surgery usually consists of an operation, under general anesthesia, to divide a portion of the internal anal sphincter muscle. This helps to eliminate the spasm, which decreases the pain and allows the fissure to heal. Complete healing sometimes occurs within weeks after the Sphincterotomy, although pain often disappears after only a few days. Some degree of postoperative incontinence for flatus or feces occurs in up to one-third of patients. Most patients would prefer to try a less invasive treatment consisting of the use of Pharmacological Sphincter Relaxants.

Chemical Sphincterotomy – Pharmacological Sphincter Relaxants

Clinical studies1 have shown that spasm of the internal anal sphincter can be relieved by using Pharmacological Sphincter Relaxants (Fissure Medications) such as calcium channel blockers (Diltiazem, Nifedipine) and topical nitrates (nitroglycerine gel) whose action on the internal anal sphincter causes it to relax and thereby eliminates the pain. Clinical experience has also shown that precise dosing of Fissure Medications and application directly to the anal mucosa (anal canal) produce optimum results.


Intra-anal application of medication to the anal mucosa has a very predictable result. It relaxes the internal anal sphincter muscle, which relieves the pain almost immediately and allows for the healing of anal fissures to begin. For this reason, use of medications is often referred to as a “Chemical Sphincterotomy”. There have been no reported cases of incontinence as a result of using Fissure Medications.