Constipation in Adults - Chronic, Functional Initial Assessment

Last updated: 23 January 2026
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History

History taking should include current bowel regimen, frequency and pattern. The use of the Bristol stool scale may help in better characterizing bowel habits and fecal consistency. A slow transit constipation may be predicted by type 1 and 2 stools from the Bristol stool scale. There is an associated abdominal pain or distress that is less severe and not the main symptom as compared with irritable bowel syndrome (IBS). Irritable bowel syndrome may be suggested by a history of predominant abdominal pain, bloating, malaise, upper gastrointestinal (GI) tract (eg dyspepsia, heartburn) and urinary symptoms, increased rectal sensation, anxiety and depression. Toileting habits (eg unusual postures on the toilet to ease stool expulsion), posterior vaginal pressure, perineum support or digitation of the rectum to ease rectal release, and failure to discharge enema fluid should also be asked. Pelvic floor dysfunction may be suggested by prolonged and excessive straining prior to elimination; when evacuatory defects are pronounced, soft stools or even enema fluid are difficult to pass; and the need for perineal or vaginal pressure or digital evacuation is also indicative of constipation. Evacuatory disorders do not respond well to laxatives.



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Medication history, including products used to relieve constipation or the use of opiates and codeine should also be asked. Inquire about the patient’s obstetric and surgical history, diet and fluid intake, lifestyle (activity level) and occupation.

Physical Examination

Assess the abdomen for swelling, pain, palpable masses, organomegaly and peristalsis. Other organ systems should be examined to rule out secondary causes of chronic constipation (eg abdominal mass from an organic cause, dry skin from hypothyroidism).

Rectal Exam

A rectal exam should be performed with the patient in the left lateral position. Inspect the perianal area to look for fissures, fistulas, external hemorrhoids, scars, anal tags, warts, blood, abscess, or stool leakage. Determine the extent of perineal descent while the patient, at rest, bears down. A reduced descent may indicate an inability to relax pelvic floor muscles during defecation. An excessive descent may show laxity of the perineum which may be caused by childbirth or several years of straining.

Digital Exam of the Rectum



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Check for fecal impaction, blood adhesion, puborectalis tenderness, anal stricture, stenosis or fissure, internal hemorrhoids, anorectal masses, and rectoceles or rectal prolapse. A lax anal orifice may suggest neurologic disorder or trauma as the cause of impaired sphincter function.  The inability or difficulty in inserting the finger into the anal canal may suggest elevated internal anal sphincter tone at rest or anal stricture. The contractile function of the puborectalis and external anal sphincter can be determined by anal tightness during contraction. Spasm of the pelvic floor may be suggested by tenderness at the posterior aspect of the rectum. A pelvic floor motor dysfunction may be indicated by an anal canal that does not relax while the patient is straining. Refer patients with normal digital rectal exam findings and persistent symptoms for anorectal testing to rule out defecatory disorders. 

Diagnosis or Diagnostic Criteria

Functional Constipation

Functional constipation has no evidence of structural or metabolic disease to account for the symptoms. It is also known as chronic idiopathic constipation.

The Rome IV diagnostic criteria for functional constipation include:

  • ≥2 of the following for >25% of bowel movements: Hard or lumpy stools, manual maneuvers to facilitate bowel movements, sensation of incomplete evacuation, sensation of anorectal blockage or obstruction, straining, <3 spontaneous bowel movements/week
  • Loose stools are rare without laxative use
  • Insufficient criteria for irritable bowel syndrome (IBS)
  • Above criteria fulfilled for the last 3 months with symptoms starting at least 6 months before diagnosis

Functional or primary constipation categories include normal or slow transit constipation, colonic inertia, pelvic floor dysfunction or outlet obstruction, and a combination of causes (eg pelvic floor dysfunction and slow transit constipation).

Screening

Alarm Signs and Symptoms (Red Flags)

If any of the following symptoms are present, a patient should undergo further diagnostic testing:

  • Abnormal physical signs (eg abdominal or rectal mass)
  • Change in stool caliber
  • Family history of colon cancer or inflammatory bowel disease (IBD)
  • Fever
  • Hematochezia
  • Iron-deficiency or unexplained anemia
  • Loss of appetite
  • Polyposis syndromes
  • Positive fecal occult blood test
  • Rapid changes in bowel habits
  • Recent onset of constipation in the elderly
  • Rectal bleeding and/or prolapse
  • Unintentional weight loss of >4.5 kg or ≥10% in 3 months
  • Vomiting