Constipation, costiveness, or irregularity, is a condition of the digestive system in which a person (or animal) experiences hard feces that are difficult to expel. This usually happens because the colon absorbs too much water from the food. If the food moves through the gastro-intestinal tract too slowly, the colon may absorb too much water, resulting in feces that are dry and hard. Defecation may be extremely painful, and in severe cases (fecal impaction) lead to symptoms of bowel obstruction. The term obstipation is used for severe constipation that prevents passage of both stools and gas. Causes of constipation may be dietary, hormonal, anatomical, a side effect of medications (e.g. some painkillers), or an illness or disorder. Treatments consist of changes in dietary and exercise habits, the use of laxatives, and other medical interventions depending on the underlying cause.

Signs and symptoms

The definition of constipation includes the following:

• infrequent bowel movements (typically three times or fewer per week)
• difficulty during defecation (straining during more than 25% of bowel movements or a subjective sensation of hard stools), or
• the sensation of incomplete bowel evacuation.

Severe cases ("fecal impaction") may feature symptoms of bowel obstruction (vomiting, very tender abdomen) and "paradoxical diarrhea", where soft stool from the small intestine bypasses the impacted matter in the colon.

Diagnosis

The diagnosis is essentially made from the patient's description of the symptoms. Bowel movements that are difficult to pass, very firm, or made up of small rabbit-like pellets qualify as constipation, even if they occur every day. Other symptoms related to constipation can include bloating, distention, abdominal pain, or a sense of incomplete emptying.

Inquiring about dietary habits may reveal a low intake of dietary fiber or inadequate amounts of fluids. Constipation as a result of poor ambulation or immobility should be considered in the elderly. Constipation may arise as a side effect of medications, including antidepressants, which can suppress acetylcholine and opiates, which can slow the movement of food through the intestines. Rarely, other symptoms suggestive of hypothyroidism may be elicited.Fact: date=February 2007

During physical examination, scybala (manually palpable lumps of stool) may be detected on palpation of the abdomen. Rectal examination gives an impression of the anal sphincter tone and whether the lower rectum contains any feces or not; if so, then suppositories or enemas may be considered. Otherwise, oral medication may be required. Rectal examination also gives information on the consistency of the stool, presence of hemorrhoids, admixture of blood and whether any tumors or abnormalities are present.