It is not clear exactly what causes esophageal spasms. Sometimes esophageal spasms start when someone eats hot or cold foods or drinks. However, they can also occur with eating or drinking. The increased release of acetylcholine may also be a factor, but the triggering event is not known.

For adults, the following may help prevent anal fissures:

- Avoiding straining when defecating. This includes treating and preventing constipation by eating food rich in dietary fiber, drinking enough water, occasional use of a stool softener, and avoiding constipating agents. Similarly, prompt treatment of diarrhea may reduce anal strain.

- Careful anal hygiene after defecation, including using soft toilet paper and cleaning with water, plus the use of sanitary wipes.

- In cases of pre-existing or suspected fissure, use of a lubricating ointment (It is important to note that hemorrhoid ointment is contraindicated because it constricts small blood vessels, thus causes a decrease in blood flow, which prevents healing.)

In infants, frequent diaper change can prevent anal fissure. As constipation can be a cause, making sure the infant is drinking enough fluids (i.e. breastmilk, proper ratios when mixing formulas) is beneficial. In infants, once an anal fissure has occurred, addressing underlying causes is usually enough to ensure healing occurs.

Several definitions have been offered:

- "Absence of normal relaxation of pelvic floor muscles during defecation, resulting in rectal outlet obstruction".

- "Malfunction (a focal dystonia) of the external anal sphincter and puborectalis muscle during defecation".

- "[...] failure of [the external anal sphincter and puborectalis] muscle[s] to relax, resulting in maintenance of the anorectal angle and the difficulty with initiating and completing bowel movements".

- "[...] failure of relaxation (or paradoxic contraction) of the puborectalis muscle sling during defaecation, attempted defaecation or straining."

One of the main causes is suggested to be excessive and repetitive straining during defecation. Other causes include weakness of the pelvic floor muscles (secondary to age related neuropathic degeneration or traumatic injury during pregnancy and labor.

Anismus is classified as a functional defecation disorder. It is also a type of rectal outlet obstruction (a functional outlet obstruction). Where anismus causes constipation, it is an example of functional constipation. Some authors describe an "obstructed defecation syndrome", of which anismus is a cause.

The Rome classification subdivides functional defecation disorders into 3 types, however the symptoms the patient experiences are identical.

- Type I: paradoxical contraction of the pelvic floor muscles during attempted defecation

- Type II: inadequate propulsive forces during attempted defecation (inadequate defecatory propulsion)

- Type III: impaired relaxation with adequate propulsion

It can be seen from the above classification that many of the terms that have been used interchangeably with anismus are inappropriately specific and neglect the concept of impaired propulsion. Similarly, some of the definitions that have been offered are also too restrictive.

Bacterial, viral, and protozoal infections may occur in the area surround the rectum. These may be the result of a sexually transmitted disease.

One review stated that the most common causes of disruption to the defecation cycle are associated with pregnancy and childbirth, gynaecological descent or neurogenic disturbances of the brain-bowel axis. Patients with obstructed defecation appear to have impaired pelvic floor function.

Specific causes include:

- Anismus and pelvic floor dysfunction

- Rectocele

- "Rectal invagination" (likely refers to rectal intussusception)

- Internal anal sphincter hypertonia

- Anal stenosis

- Fecal impaction

- Rectal or anal cancer

- Descending perineum syndrome

Liquid stool is more difficult to control than formed, solid stool. Hence, FI can be exacerbated by diarrhea. Some consider diarrhea to be the most common aggravating factor. Orlistat is an anti-obesity (weight loss) drug that blocks the absorption of fats. This may give side effects of FI, diarrhea and steatorrhea.

The incidence of anal fissures is around 1 in 350 adults. They occur equally commonly in men and women and most often occur in adults aged 15 to 40.

This may occur when there is a large mass of feces in the rectum (fecal loading), which may become hardened (fecal impaction). Liquid stool elements are able to pass around the obstruction, leading to incontinence. Megarectum (enlarged rectal volume) and rectal hyposensitivity are associated with overflow incontinence. Hospitalized patients and care home residents may develop FI via this mechanism, possibly a result of lack of mobility, reduced alertness, constipating effect of medication and/or dehydration.

Esophageal spasm is rare. Often, symptoms that may suggest esophageal spasm are the result of another condition such as gastroesophageal reflux disease (GERD) or achalasia. The symptoms can also include dysphagia, regurgitation, noncardiac chest pain, heartburn, globus pharyngis (which is a feeling that something is stuck in the throat) or a dry cough.

Obstructed defecation has many causes, so the management in any individual case is specific to the cause of the symptom. For rectal internal intususception treatment is surgical, either STARR or rectopexy. For rectocele STARR or mesh implantation. For anismus/ pelvic floor dessynergia: biofeedback exercise.

A 2008 study found that over 85% of women having a vaginal birth sustain some form of perineal trauma, and 60-70% receive stitches. A retrospective study of 8,603 vaginal deliveries in 1994 found a third degree tear had been clinically diagnosed in only 50 women (0.6%). However, when the same authors used anal endosonography in a consecutive group of 202 deliveries, there was evidence of third degree tears in 35% of first-time mothers and 44% of mothers with previous children. These numbers are confirmed by other researchers in 1999.

A study by the Agency for Healthcare Research and Quality (AHRQ) found that in 2011, first- and second-degree perineal tear was the most common complicating condition for vaginal deliveries in the U.S. among women covered by either private insurance or Medicaid.

Second-degree perineal laceration rates were higher for women covered by private insurance than for women covered by Medicaid.

Proctitis has many possible causes. It may occur idiopathically (idiopathic proctitis). Other causes include damage by irradiation (for example in radiation therapy for cervical cancer and prostate cancer) or as a sexually transmitted infection, as in lymphogranuloma venereum and herpes proctitis. Studies suggest a celiac disease-associated "proctitis" can result from an intolerance to gluten.

A common cause is engaging in anal sex with partner(s) infected with sexual transmitted diseases in men who have sex with men. Shared enema usage has been shown to facilitate the spread of Lymphogranuloma venereum proctitis.

Anal warts are irregular, verrucous lesions caused by human papilloma virus. Anal warts are usually transmitted by unprotected, anoreceptive intercourse. Anal warts may be asymptomatic, or may cause rectal discharge, anal wetness, rectal bleeding, and pruritus ani. Lesions can also occur within the anal canal, where they are more likely to create symptoms.

Two more highly common causes of functional anorectal pain are levator ani syndrome (LAS) and proctalgia fugax. Both of these conditions are thought to be caused by muscle spasms of the either the levator ani muscle or the anal sphincter muscle respectively, and may overlap symptomatically with a third less-common condition called coccygodynia which is the result of previous trauma to the coccyx bone. Stress, prolonged sitting, and constipation all seem to be associated with LAS. The majority (90%) of those reporting chronic episodes of such pain are women. Some researchers group these conditions under the medical category of "tension myalgia of the pelvic floor". Less than a third of those experiencing these conditions seek medical treatment for them. Treatment can involve the use of antispasmotic medications as well as the down-training (conscious involvement and relaxation of previously unconscious muscle movements) so that spasms occur less frequently or not at all.

Surgical treatments may be used to treat the condition, and include retro-rectal levatorplasty, post-anal repair, retro-anal levator plate myorrhaphy.

Proctitis is inflammation of the anal canal and the distal of the rectum.

Proctitis has many causes, such as infections or intercourse.

Tuberculosis proctitis can create a mucous discharge.

Causes of diffuse esophageal spasm are not well understood. It is thought, however, that many cases are caused by uncontrolled brain signals running to nerve endings. Therefore, suppression medication is often the first line therapy such as anti depressants and anti-epileptic medication are prescribed. It has also been reported that very cold or hot beverages can trigger an esophageal spasm. Avoidance therapy benefits some people, but it has not been medically proven.

The six-week period after pregnancy is called the postpartum stage. During this time, women are at increased risk of being constipated. Multiple studies estimate the prevalence of constipation to be around 25% during the first 3 months. Constipation can cause discomfort for women, as they are still recovering from the delivery process especially if they have had a perineal tear or underwent an episiotomy. Risk factors that increase the risk of constipation in this population include:

- Damage to the levator ani muscles (pelvic floor muscles) during childbirth

- Forceps-assisted delivery

- Lengthy second stage of labor

- Delivering a large child

- Hemorrhoids

Hemorrhoids are common in pregnancy and also may get exacerbated when constipated. Anything that can cause pain with stooling (hemorrhoids, perineal tear, episiotomy) can lead to constipation because patients may withhold from having a bowel movement so as to avoid pain.

The pelvic floor muscles play an important role in helping pass a bowel movement. Injury to those muscles by some of the above risk factors (examples- delivering a large child, lengthy second stage of labor, forceps delivery) can result in constipation. Women sometimes get enemas during labor that can also alter bowel movements in the days after having given birth. However, there is insufficient evidence to make conclusions about the effectiveness and safety of laxatives in this group of people.

Several techniques are used to reduce the risk of tearing, but with little evidence for efficacy. Antenatal digital perineal massage is often advocated, and may reduce the risk of trauma only in nulliparous women. ‘Hands on’ techniques employed by midwives, in which the foetal head is guided through the vagina at a controlled rate have been widely advocated, but their efficacy is unclear. Waterbirth and labouring in water are popular for several reasons, and it has been suggested that by softening the perineum they might reduce the rate of tearing. However, this effect has never been clearly demonstrated.

A 2014 meta-analysis of three small trials evaluating probiotics showed a slight improvement in management of chronic idiopathic constipation, but well-designed studies are necessary to know the true efficacy of probiotics in treating this condition.

Children with functional constipation often claim to lack the sensation of the urge to defecate, and may be conditioned to avoid doing so due to a previous painful experience. One retrospective study showed that these children did indeed have the urge to defecate using colonic manometry, and suggested behavioral modification as a treatment for functional constipation.

High-voltage pulsed galvanic stimulation (HGVS) has been shown to be of prophylactic benefit, to reduce the incidence of attacks. The patient is usually placed in the left lateral decubitus position and a sterile probe is inserted into the anus. The negative electrode is used and the stimulator is set with a pulse frequency of 80 to 120 cycles per second. The voltage (intensity) is started at 0, progressively raised to a threshold of patient discomfort, and then is decreased to a level that the patient finds comfortable. As the patient's tolerance increases, the voltage can be gradually increased to 250 to 350 Volts. Each treatment session usually lasts between 15 and 60 minutes. Several studies have reported short-term success rates that ranged from 65 to 91%.

Traditional remedies have ranged from warm baths (if the pain lasts long enough to draw a bath), warm to hot enemas, relaxation techniques, and various medications.

Yoga pose "downward facing dog" -Adho Mukha Svanasana, or modification from it seems to help to relax the muscles and ease the pain. The idea of the yoga pose is that the position will force the muscles to relax and therefore tension will relieve over time. Also relaxing one's jaw muscles will help to relax the muscles in rectal area, method used by women giving birth.

In patients who suffer frequent, severe, prolonged attacks, inhaled salbutamol has been shown in some studies to reduce their duration.

The use of botulinum toxin has been proposed as analgesic, and low dose diazepam at bedtime has been suggested as preventative.

The most common approach for mild cases is simply reassurance and topical treatment with calcium-channel blocker (diltiazem, nifedipine) ointment, salbutamol inhalation and sublingual nitroglycerine.For persistent cases, local anesthetic blocks, clonidine or Botox injections can be considered. Supportive treatments directed at aggravating factors include high-fiber diet, withdrawal of drugs which have gut effects (e.g., drugs that provoke or worsen constipation including narcotics and oral calcium channel blockers; drugs that provoke or worsen diarrhea including quinidine, theophylline, and antibiotics), warm baths, rectal massage, perineal strengthening exercises, anti-cholinergic agents, non-narcotic analgesics, sedatives or muscle relaxants such as diazepam.

Although SRUS is not a medically serious disease, it can be the cause of significantly reduced quality of life for patients. It is difficult to treat, and treatment is aimed at minimizing symptoms.

Stopping straining during bowel movements, by use of correct posture, dietary fiber intake (possibly included bulk forming laxatives such as psyllium), stool softeners (e.g. polyethylene glycol, and biofeedback retraining to coordinate pelvic floor during defecation.

Surgery may be considered, but only if non surgical treatment has failed and the symptoms are severe enough to warrant the intervention. Improvement with surgery is about 55-60%.

Ulceration may persist even when symptoms resolve.