The anus is the external opening of the rectum (the final portion of the colon). A rip or tear in the skin of the anal canal is called an anal fissure. Anal fissures may result in anal bleeding, which is noticeable on toilet paper or in stool in the toilet. Pain is associated with both acute and chronic anal fissures. In general, the fissures extend from the anal opening and are located posteriorly in the midline. The depth of the fissure varies; it may be superficial or as deep as the underlying sphincter muscle (the muscle that holds the anus closed). An anterior fissure is very rare (10% of female and 1% of male cases).
Anal fissures are generally caused by stretching of the anal mucosa (moist tissue). This may occur because of constipation, passing hard and/or large stools, prolonged diarrhea, decreased blood flow to the area (as seen occasionally in older adults), childbirth, dietary choices, or inflammatory bowel disorders such as Crohn's disease. Anal fissures occur commonly in infants. Less common causes include anal sex and diseases such as cancer, HIV, tuberculosis, and syphilis.
The drug nicorandil (a potassium-channel activator) may increase the risk of anal fissure, although the available research is limited.
Anal fissures may affect all age groups, with an equal incidence in both sexes. In the United States, over 200,000 new cases of anal fissure are reported, and 40% persist for months to years. In pregnancy, up to one-third of women develop anal fissures and external hemorrhoids. Constipation and dyschezia (retaining stool in the rectum) during pregnancy are the main risk factors for their development.
Of current interest is the development of surgical treatments with fewer complications than lateral internal sphincterotomy (LIS), the current treatment of choice for chronic fissures. LIS generally has a high success rate. However, complications may include postsurgical pain, slow healing of the incision, and development of acute (during the surgical recovery period) and usually mild anal incontinence (lack of control of the bladder), including the inability to control gas, fecal soiling, and fecal loss.
Diagnosis is usually initiated because of bleeding or pain associated with defecation. The healthcare provider can usually diagnose an anal fissure based on medical history and a rectal or visual exam.
A rectal exam may involve the insertion of a gloved finger into the anal canal. However, this is often too painful, and a visual exam only may be conducted. The visual exam may employ a short, lighted tube called an anoscope.
If the tear is visible, a diagnosis can be made. If the tear is not visible, a sample of the rectal tissue can be taken.
Generally, other tests are not needed. However, if signs and symptoms also suggest an underlying inflammatory bowel disorder or colorectal cancer, or if the healthcare practitioner wants to rule out other disorders, other tests may be conducted. These include flexible sigmoidoscopy (the insertion of a thin, flexible tube with a tiny video camera into the sigmoid (bottom part of the colon)), colonoscopy (the insertion of a thin, flexible tube with a tiny video camera into the entire colon), and anal manometry (the insertion of a thin, flexible tube into the anus and rectum for the expansion of a balloon to determine the tightness of the anal sphincter and function of the rectum).
Complications of anal fissures may result from recurrence, inability to heal, or from treatments used. The risk of a subsequent anal fissure is increased in persons who have had a previous anal fissure.
The main complication associated with acute fissures is an inability to heal. An anal fissure that does not heal within a few weeks becomes chronic. These anal fissures become deeper and form ulcers. If the anal fissure extends into the internal anal sphincter muscle (the muscle that holds the anus closed) and spasms, it may impair blood supply to the fissure, reducing the ability to heal. In the case of a chronic, nonhealing ulcer, infection by fecal bacteria (bacteria in the stool) is possible.
An increased risk of anal cancer is associated with previous development of anal fissures.
Complications may also occur from treatments used for anal fissure. Surgery is often used to treat a chronic anal fissure. Surgery for chronic fissure may result in the development of acute (during the surgical recovery period) or chronic, usually mild anal incontinence (lack of control of the bladder), including inability to control gas, fecal soiling, and fecal loss. Other complications of surgery include postoperative pain or slow healing of the incision, hematoma or ecchymosis (bruising), abscesses, hemorrhage, and urinary incontinence (lack of control of the bladder), as well as recurrent fissures.
Complications of botulinum toxin (another potential treatment) include gas or fecal incontinence, as well as blood clotting or bruising around the anus. Flu-like symptoms and swelling of the epididymis (the tube that connects the testicle with the vas deferens) have been reported rarely. Adverse effects are considered short-term and reversible.
Complications of topical nitroglycerin (occasionally used to relax the anal sphincter muscle) include headaches, low blood pressure, and dizziness. Anal itch and allergic dermatitis have been reported rarely.
Complications of increasing fiber in the diet include gas or bloating.
In infants, those with a previous episode of abscess or pus at the time of surgery were more likely to have recurring anal fissures.
Most fissures heal within a few weeks and do not require specific treatment. If treatment is necessary, first-line treatments are generally home-based. If the fissure does not heal and becomes chronic, further treatment, such as nonsurgical and surgical procedures, becomes necessary.
In infants, it is advised to change diapers frequently and ensure the infant is receiving enough fluids (breast milk or adequate water added to formula).
Home care methods:
Home care methods can be used to treat most acute anal fissures. These include gentle cleansing, increased intake of fluids, regular exercise of 30 minutes daily on most days of the week, applying petroleum jelly to the area, using a stool softener, avoiding straining during a bowel movement, increasing fiber in the diet or use of fiber supplements, or using a sitz bath. Sitz baths involve soaking in warm water for 10-20 minutes several times daily. Fiber in the diet can be increased by increasing consumption of fruit, vegetables, beans, grains, and nuts. Fiber supplements include psyllium.
Nonsurgical treatments (medications):
In some cases, medications may be necessary. In general, these medications are used to relax the muscles or decrease pain around the anus. Medications include muscle relaxants or analgesic or anesthetic numbing creams, which are applied to the skin around the fissure.
Examples of creams include topical nitroglycerin, calcium channel blockers (nifedipine or diltiazem), and zinc oxide. Nitroglycerin cream increases blood flow to the fissure, promoting healing. Complications of topical nitroglycerin include headaches, low blood pressure, and dizziness. It is generally recommended that nitroglycerin ointment be applied while in a seated or lying down position to prevent dizziness. Exercising immediately afterwards is generally not advised. Nitroglycerin ointment is not advised within 24 hours in men using erectile dysfunction medications (sildenafil, tadalafil, vardenafil) due to the potential for effects on blood pressure.
Injection of onabotulinumtoxinA (botulinum toxin; Botox) into the anal sphincter (the muscle in the anus) is occasionally used to relax the anal sphincter by initially paralyzing it. Complications include pain at the injection site or anal incontinence (gas and fecal).
If the fissure does not heal within a few months, surgery may be necessary. Examples of surgical treatment for anal fissure include anal stretch (Lord's operation) or lateral sphincterotomy (LIS). The goal of these surgeries is to reduce sphincter spasm, allowing a return to normal blood supply.
Lateral internal sphincterotomy (LIS): LIS generally has a high success rate. It is usually a same-day surgery, with the patient under general anesthesia. It involves partially dividing the internal anal sphincter. This allows the blood supply to the area to improve and slightly weakens the sphincter. Recovery is often within one week. Complications may include postsurgical pain, slow healing of the incision, and the development of acute (during the surgical recovery period) and usually mild anal incontinence, including keyhole deformities (where the anal canal resembles an old-fashioned key) and inability to control gas, fecal soiling, and fecal loss. The use of three stitches may reduce complications associated with LIS.
Dermal flap coverage: Dermal flap coverage (use of skin flaps for coverage of the fissure) is of interest in the surgical treatment of anal fissures due to reduced complications following this surgery.
Anal dilation: Anal dilation involves stretching of the anal canal (Lord's operation). It is less commonly performed than LIS. Both fecal and gas incontinence are common adverse events of this procedure.
Other: Less common surgical treatments include anal advancement flap (diseased tissue cut away and good tissue sewn over the area), tailored anal sphincterotomy (sphincterotomy as described as above, but more sphincter is preserved), and fissurectomy (removal of the fissure).
Arginine: Arginine is a semiessential amino acid. In the body, it is converted to nitric oxide and aids in vasodilation (dilation of the blood vessels). Arginine also triggers the body to make protein and has been studied for healing wounds. Early research suggests that arginine helps heal chronic anal fissures, but additional studies are needed.
Use caution in patients with bleeding disorders or those taking drugs that may increase the risk of bleeding. Use caution in patients with diabetes or hypoglycemia or those taking agents that affect blood sugar. Use caution in patients with impaired kidney function, those at risk for high blood potassium (including those with diabetes), or those using drugs that elevate potassium levels (including potassium-sparing diuretics and potassium supplements). Use caution with phosphodiesterase inhibitors (such as sildenafil [Viagra®]) in postmenopausal patients, in patients with herpes virus, and in individuals at risk for headaches. Use caution in patients with immunological disorders, acrocyanosis, sickle cell anemia, hyperchloremic acidosis, or guanidinoacetate methyltransferase (GAMT) deficiency. Avoid in those with low blood pressure or those using blood-pressure lowering agents, in patients with asthma or breast cancer, in those at risk for or with a history of heart attack, or in those using nitrates or spironolactone. Avoid in pregnant or breastfeeding women. Avoid with known allergy or sensitivity to arginine.
Ayurveda: Ayurveda originated in ancient India more than 5,000 years ago and is potentially the world's oldest system of natural medicine. It is an integrated system of specific theories and techniques that uses diet, herbs, exercise, meditation, yoga, and massage or bodywork. The goal of Ayurveda is to achieve optimal health on all levels: physical, psychological, and spiritual. There is some evidence that a traditional Ayurvedic treatment using specially prepared alkaline threads (ksharasutra or Ayurvedic setons) to achieve gradual cauterization may provide an effective alternative to surgery in patients being treated for anal fistulas.
Ayurvedic herbs should be used cautiously, because they are potent. Some constituents can be potentially toxic if taken in large amounts or for a long time. Some herbs imported from India have been reported to contain high levels of toxic metals. Ayurvedic herbs can interact with other herbs, foods, and drugs. A qualified healthcare professional should be consulted before taking Ayurvedic herbs. Use guggul cautiously with peptic ulcer disease. Avoid sour food, alcohol, and heavy exercise. Mahayograj guggul should not be taken for long periods of time. Pippali (Piper longum) should be taken with milk and avoided with asthma. Avoid sweet flag, and avoid amalaki (Emblica officinalis) at bedtime. Avoid Terminalia hebula (harda) if pregnant. Avoid Ayurveda with traumatic injuries, acute pain, advanced disease stages, and medical conditions that require surgery.
Clove: Clove is widely cultivated in Indonesia, Sri Lanka, Madagascar, Tanzania, and Brazil. It is used in limited amounts in food products and is used as a fragrance, flavoring agent, and antiseptic. There is some evidence that a clove oil cream may aid in relief from anal fissures.
Use cautiously with seizure disorders and kidney or liver dysfunction. Use cautiously in patients with low blood pressure or in those taking drugs that lower blood pressure. Use cautiously in patients taking estrogen. Use cautiously in patients with autoimmune disorders or in those taking drugs that suppress the immune system. Avoid if pregnant or breastfeeding. Avoid if allergic to balsam of Peru, clove, eugenol, or some licorice and tobacco (clove cigarette) products. Avoid with bleeding disorders and in pediatric patients. Avoid use of undiluted clove oil on the skin.
Psyllium: Psyllium, also referred to as ispaghula or isphagula, is derived from the husks of the seeds of Plantago ovata. Psyllium contains a high level of soluble dietary fiber and is the chief ingredient in many commonly used bulk laxatives, including products such as Metamucil® and Serutan®. There is some evidence that psyllium reduces the number of surgeries necessary to heal anal fissures.
Avoid if allergic or hypersensitive to psyllium, ispaghula, or English plantains (Plantago lanceolata). Avoid in patients with esophageal disorders, gastrointestinal atony, fecal impaction, gastrointestinal tract narrowing, swallowing difficulties, or previous bowel surgery. Avoid ingestion of psyllium-containing products in individuals with repeated or prolonged psyllium exposure. Prescription drugs should be taken one hour before or two hours after psyllium. Adequate fluid intake is required when taking psyllium-containing products. Use cautiously with blood thinners, antidiabetic agents, carbamazepine, lithium, potassium-sparing diuretics, salicylates, tetracyclines, nitrofurantoin, calcium, iron, vitamin B12, other laxatives, tricyclic antidepressants (amitriptyline, doxepin, and imipramine), antigout agents, anti-inflammatory agents, hydrophilic agents, and chitosan. Use cautiously with diabetes and kidney dysfunction. Use cautiously if pregnant or breastfeeding.
Historical or theoretical uses that lack sufficient evidence:
Bovine cartilage: Bovine cartilage, as a dietary supplement, typically is a preparation of bovine tracheal cartilage. There is a lack of research on the effectiveness of this agent for anal fissures.
Avoid if allergic or hypersensitive to bovine cartilage or any of its constituents. Use cautiously with cancer, kidney failure, or liver failure. Avoid if pregnant or breastfeeding.
Cascara sagrada: Cascara is obtained from the dried bark of Rhamnus purshiana, both a medicinal and poisonous plant. It is found in Europe, western Asia, and North America (from northern Idaho to the Pacific coast in mountainous areas). There is a lack of research on the effectiveness of this agent for anal fissures.
Cascara was formerly approved by the U.S. Food and Drug Administration (FDA) as safe and effective, but this designation was removed in 2002 because of lack of supporting evidence. Avoid if allergic or hypersensitive to cascara. Use cautiously in children, due to the risk of electrolyte loss, specifically low levels of potassium. Use cascara cautiously in elderly patients. Avoid using cascara with nausea or vomiting, inflammatory bowel disease, appendicitis, intestinal obstruction, acute intestinal inflammation, Crohn's disease, ulcerative colitis, appendicitis, ulcers, or abdominal pain of unknown origin. Avoid with other laxatives. Avoid if pregnant or breastfeeding. Be aware that prolonged use of cascara may lead to dependence and tolerance.
Ozone therapy: Ozone molecules are composed of three oxygen atoms (represented as O3). Ozone exists high in the earth's atmosphere and absorbs solar radiation. Ozone therapists have used different forms of ozone to treat a wide variety of conditions. There is a lack of research on the effectiveness of this treatment for anal fissures.
Autohemotherapy has been associated with transmission of viral hepatitis and with a possible case of dangerously lowered blood cell counts. Insufflation of the ear carries a risk of tympanic membrane ("ear drum") damage, and colon insufflation may increase the risk of bowel rupture. Consult a qualified healthcare professional before undergoing any ozone-related treatment.
Peony: Peony has been used in traditional Chinese medicine (TCM) prescriptions for centuries. There is a lack of research on the effectiveness of this agent for anal fissures.
Avoid if allergic or sensitive to peony. Avoid with bleeding disorders or if taking drugs, herbs, or supplements that increase bleeding risk. Use cautiously with estrogen-sensitive cancers or if taking drugs, herbs, or supplements with hormonal activity. Avoid if pregnant or breastfeeding.
Rhubarb: Chinese herbalists have relied on rhubarb rhizomes and roots for thousands of years. The rhizomes and roots contain powerful anthraquinone and tannin compounds that act as stimulant laxatives and astringents, respectively. There is a lack of research on the effectiveness of this agent for anal fissures.
Avoid if allergic or hypersensitive to rhubarb, its constituents, or related plants from the Polygonaceae family. Avoid using rhubarb for more than two weeks, because it may induce tolerance in the colon, melanosis coli, laxative dependence, pathological alterations to the colonic smooth muscles, and substantial loss of electrolytes. Avoid with atony, colitis, Crohn's disease, dehydration with electrolyte depletion, diarrhea, hemorrhoids, insufficient liver function, intestinal obstruction or ileus, irritable bowel syndrome, menstruation, renal disorders, ulcerative colitis or urinary problems. Avoid handling rhubarb leaves, as they may cause contact dermatitis. Avoid rhubarb in children under age 12, due to water depletion. Use cautiously with bleeding disorders, cardiac conditions, coagulation therapy, constipation, history of kidney stones, or thin or brittle bones. Use cautiously if taking antipsychotic drugs or oral drugs, herbs, or supplements (including calcium, iron, and zinc).
Senna: Senna (Cassia senna) is an ingredient found in several commercial laxative products. It is a U.S. Food and Drug Administration (FDA)-approved nonprescription drug. Both the leaves and the fruit (pods) of senna are stimulant laxatives. There is a lack of research on the effectiveness of this agent for anal fissures.
Avoid with known allergy or hypersensitivity to senna, its constituents, or members of the Fabaceae family. Use cautiously in patients who have had an obstruction of the gastrointestinal tract, according to expert opinion. Use cautiously in patients with hemorrhoids, stomach ulcers, or inflammatory bowel conditions. Use cautiously in patients with a history of gallstones. Use cautiously in patients taking diuretics or other laxatives, as additional potassium depletion may occur. Use cautiously in patients using anticoagulants (blood thinners), due to the potential for excessive bleeding to occur. Use cautiously in patients taking digoxin, as increased side effects may occur. Use cautiously in children less than 12 years of age. Avoid long-term use of senna, due to the potential for side effects, some of which may be serious. Experts suggest that senna should not be used for longer than 7-10 days. Chronic use of laxatives may lead to "lazy-bowel syndrome," in which the stomach and intestines gradually lose the ability to contract without being stimulated by the laxative.
Slippery elm: Slippery elm inner bark has been used historically in wound healing. There is a lack of research on the effectiveness of this agent for anal fissures.
Avoid if allergic or hypersensitive to slippery elm. Avoid if pregnant or breastfeeding.
Tamanu: Tamanu is a large tropical tree native to Polynesia and Southeast Asia. The oil from tamanu nuts has a long history of traditional medical use as a topical anti-inflammatory agent and for many skin conditions. There is a lack of research on the effectiveness of this agent for anal fissures.
Avoid if allergic or hypersensitive to tamanu or any other plants in the same genus (Calophyllum) or family (Clusiaceae). Use cautiously with bleeding disorders or if using anticoagulants. Use cautiously if using sedatives or operating heavy machinery. Avoid if pregnant or breastfeeding, due to a lack of scientific data.
Anal fissures can be prevented in infants by ensuring adequate intake of fluids and water added to formulas, as well as frequent diaper changes.
In adults, anal fissure can be prevented by the following: avoiding straining during defecation, avoiding constipation and/or passage of hard or large stools, avoiding prolonged diarrhea, avoiding chronic wetness around the anus, and avoiding rough toilet paper or other harsh types of anal hygiene or rectal irritation. Constipation can be avoided by increasing fiber and fluid intake in the diet and decreasing caffeine intake.
If a fissure is suspected, a lubricating ointment can prevent worsening.
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Abramowitz L, Batallan A. [Epidemiology of anal lesions (fissure and thrombosed external hemorroid) during pregnancy and post-partum]. Gynecol Obstet Fertil. 2003 Jun;31(6):546-9.
Andiran F, Dayi S, Mete E. Cows milk consumption in constipation and anal fissure in infants and young children. J Paediatr Child Health. 2003 Jul;39(5):329-31.
Hancke E, Rikas E, Suchan K, et al. Dermal flap coverage for chronic anal fissure: lower incidence of anal incontinence compared to lateral internal sphincterotomy after long-term follow-up. Dis Colon Rectum. 2010 Nov;53(11):1563-8.
Kang GS, Kim BS, Choi PS, et al. Evaluation of healing and complications after lateral internal sphincterotomy for chronic anal fissure: marginal suture of incision vs. open left incision: prospective, randomized, controlled study. Dis Colon Rectum. 2008 Mar;51(3):329-33.
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Anal fissures are generally caused by stretching of the anal mucosa. In adults, this may occur because of constipation, passing hard and/or large stools, straining during defecation, prolonged diarrhea, pregnancy, childbirth, or inflammatory bowel disorders such as Crohn's disease.
Less common causes of anal fissures in adults include anal sex and diseases such as cancer, HIV, tuberculosis, and syphilis.
In older adults, decreased blood flow to the anus increases the risk of nonhealing wounds.
In infants, constipation and infrequent diaper changes are common causes of anal fissures.
Risk factors in the development of anal fissures include chronic constipation, passage of hard and/or large stools, straining during defecation, and prolonged diarrhea.
Diets low in fiber and water may increase the risk of straining during defecation and constipation and thus may increase the risk of anal fissure development.
Diets high in agents that may increase the risk of constipation, including caffeine, may increase the risk of straining during defecation and of constipation and thus may increase the risk of anal fissure development.
Spicy foods may aggravate symptoms of anal fissures.
Aging is a risk factor for anal fissures. Aging is often accompanied by decreased blood flow to the anus, increasing the risk of nonhealing wounds.
The potassium-channel activator nicorandil may increase the risk of anal fissure. Use of this agent is associated with increased anal ulcerations. However, the available research is limited.
Pregnancy and childbirth may increase the risk of anal fissures. In pregnancy, up to one-third of women develop anal fissures and external hemorrhoids. Constipation and dyschezia (retaining stool in the rectum) during pregnancy may be the main risk factors during pregnancy.
In infants, risk factors include infrequent diaper changes and constipation, often due to inadequate fluid intake. Infants with a previous episode of abscess or pus at the time of surgery were more likely to have recurring anal fissures. Early introduction of cow's milk may increase constipation and therefore the risk of anal fissures.
Other risk factors in adults include harsh anal hygiene (rough toilet paper), chronic wetness around the anus, rectal irritation, bariatric procedures for obesity, constant saddle vibration (in professional mountain bikers), the use of bidet toilets, sexual abuse, and inflammatory bowel disorders such as Crohn's disease.
General: Both acute and chronic anal fissures are possible. Fissures may be considered primary (with no known trigger) or secondary (there is a likely trigger).
Acute vs. chronic anal fissures: Acute anal fissures are commonly associated with severe pain after defecation. Acute anal fissures are generally superficial or shallow and may be hard to detect visually. Acute fissures generally heal within days to weeks. Chronic anal fissures, lasting longer than about six weeks, are generally associated with less pain than the acute form of the disorder. These anal fissures become deeper (forming an ulcer), and healing is more difficult or does not occur. Internal anal sphincter muscle spasm impairs blood supply to the fissure, reducing the ability to heal. In the case of a chronic, nonhealing ulcer, infection by fecal bacteria is possible.
Primary vs. secondary anal fissures: Primary anal fissures are most commonly located on the posterior anal midline and have no obvious trigger. A small percentage of primary anal fissures are located on the anterior midline. Secondary anal fissures are a result of inflammatory bowel disease, previous anal surgery, and disease (e.g., venereal diseases, skin disorders, infections, or tumors). Infections associated with secondary anal fissures may include tuberculosis, herpes, cytomegalovirus, Chlamydia, Haemophilus ducreyi, and HIV. The location of secondary anal fissures may not be typical (lateral, etc.).
The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.