Burning Anus, Rectum, Burning Sensation after a Bowel Movement

A burning sensation in the anus or during and after a bowel movement is not an uncommon experience and every person may experience it at some point in time. Often it is related to eating spicy foods or during and after a bout of gastroenteritis. At other times burning is sign of proctitis, which in inflammation of the anus and rectum due to a host of causes. Skin diseases may also spread around the anus and in some cases, even into the anal canal.

A single episode of burning in the anus or following a bowel movement, or even a day or two of irritation, is not always associated with a disease. However, a burning sensation accompanied by rectal bleeding, mucus or blood in the stool, abnormal bowel habit like persistent diarrhea or chronic constipation, should be investigated for a host of bowel diseases.

The rectum is usually empty of feces until the relevant defecation reflexes commence. Once the rectum  fills with fecal matter and if the situation is appropriate, defecation will occur. The distension of the rectum when it fills with feces, coupled with the passage of feces through the anal canal can elicit a number of sensations including pain, burning or itching if the surrounding tissue is irritated. The itching sensation itself cannot be felt in the rectum, but with deeper anal itching, it is often mistaken for itching in the rectum.

Causes of a Burning Anus

Burning in the anus or rectum, or a burning sensation during or after a bowel movement may be a symptom of a number of conditions. Some of the causes may include :

Spicy Foods

The chemicals present in spicy foods typically causes irritation of the tongue mucosa where it detected as being ‘hot’. This effect persists as it travels through the gut. If these irritants are not degraded or neutralized by the time it reaches the rectum, it will cause local irritation of the anal mucosa. The inflammatory response also causes redness and sometimes swelling of the affected area. The most common irritant foods is capsicin present in chilli and peppers but a host of other chemicals in foods can have a similar reaction. The burning sensation usually starts after a bowel movement and persists for a period of time afterwards. Spicy foods may also cause mild diarrhea which can irritate the anus and lead to burning.

Anal Itching

Pruritis ani (itchy anus) is often associated with excessive wiping, certain foods and sometimes skin diseases and infectious conditions. Repeated scratching of the anus due to itching may lead to a burning sensation. This is often aggravated after a bowel movement.

Poor Hygiene

Inadequate wiping and bathing can cause local irritation of the anal mucosa due to the presence of fecal matter and large populations of bowel bacteria. Itching is often reported and with secondary skin infections, a burning sensation may also be apparent. These sensations will ease with practicing proper hygiene and treating any complications that may have arisen.

Hemorrhoids

Hemorrhoids are the swelling and weakening of the rectal veins, often associated with chronic constipation or diarrhea. It may also arise for other reasons. Hemorrhoids, also known as piles, is a common rectal condition and presents with a host of symptoms like rectal bleeding after a bowel movement, especially upon wiping, itching and burning. It is aggravated after a bowel movement but the discomfort (burning, itching, pain) usually persists throughout the day to varying degrees.

Anal Fissures

Minute tears in the lining of the anal mucosa often arise with chronic constipation and diarrhea. As with hemorrhoids, there are a host of other causes that may be responsible. Burning and pain are typical of anal fissure and tend to exacerbate after a bowel movement and persist afterwards for a period of time. Rectal bleeding and anal itching are often present as well.

Fecal Incontinence

With fecal incontinence, impairment of bowel control allows small quantities of the liquid fecal matter or a complete bowel movement to pass out of the anus involuntarily. Burning in the anus or rectum may be a symptom of one of the causes of fecal incontinence. It may also be related to the presence of fecal matter and bowel bacteria which is not removed from the area as a person may be unaware of the event.

Bowel Problems

A number of diseases that affect the colon, rectum and anus can cause a burning sensation. Inflammation or ulceration of the bowel  lining may also cause a number of other symptoms like rectal bleeding, pelvic and/or abdominal pain, mucus in the stool and abnormal bowel movements like diarrhea or constipation may also be present. Often these other symptoms may also lead to hemorrhoids, anal fissures or incontinence which contributes to burning of the anus or rectum.

  • Inflammatory bowel disease
  • Constipation –  impacted feces
  • Irritable bowel syndrome (IBS)
  • Gastroenteritis
  • Rectal prolapse

Other complications like a perianal abscess or anal fistula may also cause burning in the anus or rectum and needs immediate medical attention.

Other Burning Anus Causes

There are host of other causes that may also contribute to a burning sensation in the rectum and around the anus which may or may not be associated with bowel movements. Some of the causes may include :

  • Skin diseases
    • seborrheic dermatitis
    • psoriasis
    • eczema
    • pilonidal cyst
  • Infections
    • Sexually transmitted infections (STIs) – genital herpes, gonorrhea, chlamydia
    • Other infections – intestinal parasites, candida (immunocompromised patients), streptococcal dermatitis, tinea crura/corporis (fungal)