Most of us do not think about the urging sensation we feel when we need to have a bowel movement. It is a normal part of life that most of us experience daily. However, there are cases where urging can be considered to be abnormal, like when it is constant and is not relieved with passing stool.
What is bowel urging?
Bowel urging is the sensation a person feels when they need to pass stool. It varies in intensity, usually starting off mild and then gradually intensifying. Urging serves as a signal to find an appropriate setting in order to pass stool. As the stool is being evacuated the urging subsides and eventually ceases altogether after the rectum is emptied of stool. This type of urging is normal and is a result of stretching of the lower colon and rectum.
Normally when the lower colon is filled with stool, the colon wall stretches and this signals the need to pass stool. The stool is then pushed into the rectum and the rectal walls stretch. At this point the urging sensation becomes intense and a person usually responds to this sensation by going to the toilet. Strong urging coincides with the involuntary anal sphincter relaxing. Once prepared to pass stool, a person relaxes the voluntary anal sphincter and stool is evacuated. The rectal wall is no longer stretched and the urging subsides.
Abnormal and Excessive Urging
There are instances where there is abnormal urging. It may be excessive where the sensation of urging continues even after a person passes stool. There may also be the urge to pass stool but upon trying to defecate a person is unable to have a bowel movement. Abnormal and excessive urging is a symptom of some underlying disease, usually conditions that affect the lower colon, rectum and anus. The constant urging only resolves once the underlying condition is appropriately treated.
Why does abnormal urging occur?
Abnormal urging occurs when the bowel wall is excessively stretched, irritated or inflamed, or when the nerves to lower colon and rectum are abnormally stimulated.This can arise with a number of diseases. However, there instances where abnormal urging is not due to any physiological abnormality but may occur with psychological factors. Anxiety and psychological stress may cause some people to feel the urge to pass stool and this eases when the cause of the stress is removed.
Causes of Abnormal and Constant Urging
There are a number of different causes of abnormal and constant urging to pass stool. Some of the more likely causes have been discussed below. It should be investigated and diagnosed by a medical professional as some serious conditions such as colorectal cancer can also present with a constant urge to pass stool.
Infections are one of the common causes of abnormal urging. It is usually acute and accompanied by other symptoms like nausea, vomiting, diarrhea and abdominal cramping. Gastroenteritis is a common infectious bowel disorder that is usually acute. Most of the time it is caused by viruses but bacteria and protozoa (single-celled parasites) may also be responsible for gastroenteritis. Sometimes toxins produced by these microbes can also be responsible for the bowel inflammation.
Inflammatory bowel disease (IBD) is an autoimmune conditions where the lower colon and rectum may be come inflamed. Apart from diarrhea, blood and mucus in the stool, a person may also experience constant urging. Hemorrhoids is a condition where the vessels of the rectum and anus becomes inflamed and apart from burning, itching and blood in the stool there is also a constant urge to pass stool. Diverticulitis is another condition where there may be constant urging. This inflammation of the diverticula can also sometimes be due to an infection.
Any injury to the anus, rectum or lower part of the colon may cause a constant urge to pass stool. Injuries to these areas may arise with diagnostic procedures like a colonoscopy, insertion of other objects through the anus and even after surgery. Proctitis is an inflammatory condition of the rectum and anus that can occur with trauma and infections. People who suffer with anal itching may also be prone to injuring this area by scratching with the fingers.
A constant urge to defecate is one of the symptoms that accompany constipation. It may not always be present with constipation and despite the feeling, a person may still not be able to pass stool. The urge may persist even after passing stool as the hard stool that is characteristic of constipation as well as the straining to have a bowel movement irritates the rectum and anus. In addition the presence of hemorrhoids which affects many people with chronic constipation can further contribute to a persistent bowel urging.
Diarrhea is a symptom that may arise with a host of other symptoms. Most of the diarrhea is acute and due to infections as is the case with viral gastroenteritis. In addition, the constant passing of stool can cause irritation of the lower colon and rectum, as well as contribute to conditions like hemorrhoids. The urge to pass stool may persist despite repeated bowel movements.
A functional bowel disorder is where there is no disease of the bowels but there is abnormalities in the function of the bowels thereby leading to symptoms. Irritable bowel syndrome (IBS) is a common functional bowel disorder. In IBS there is no disease of the bowels but the movement through the bowels is abnormal. It can be too fast giving rise to diarrhea as in IBS with diarrhea, or too slow thereby resulting in constipation as is the case in IBS with constipation. Constant urging is more likely to arise during acute flareups.
A bowel obstruction can lead to constant urging as stool accumulates in the colon and rectum thereby stretching the walls of these parts of the gut. Fecal impaction is where the stool becomes hard and stuck in the colon and rectum. This is more likely to arise as a complication of constipation. The colon walls can stretch excessively leading to a condition known as megacolon. There is a risk of colon rupture in severe cases. Urging is due to this abnormal stretching but a person is unable to pass stool as a result of the obstruction.