Overview

Constipation is a common condition in which bowel movements are unusually infrequent, hard, or dry.

There is considerable variation in bowel habits that are considered "normal" in North American society, but physiologists believe that ideally a person should have a bowel movement within an hour after each meal, as the enteric nervous system that controls movement of the bowels produces a strong wave of peristalsis in response to the incoming bolus of food.

Please see conventional, complementary, and alternative medical treatments for important background information regarding the different types of medical treatments discussed on this page. Naturopathic, Complementary, and Alternative treatments that may be considered include:


Signs and Symptoms

  • Extended time between bowel movements.
  • Painful defecation. In children, clenching buttocks, rocking up and down on toes, and turning red in the face are signs of trying to hold in a bowel movement.
  • Feeling of incomplete evacuation, bloating, or abdominal fullness.
  • Hard, dry stools.
  • Paradoxically, fecal impaction can lead to a thin watery stool as small quantities of freshly formed watery or soft stool leak around the impaction.
  • Nausea, vomiting, headaches, and loss of mental clarity due to accumulation of toxins.

Constipation is characterized by bowel movements that look like types 1 to 3 on the Bristol Stool Form Scale, as shown below [Lewis1997  🕮 ].

Bristol Stool Form Scale
Type Description Example
1 Separate hard lumps Stool
2 Sausage-like but lumpy Stool
3 Sausage-like but with cracks in the surface Stool
4 Smooth and soft (ideal) Stool
5 Soft blobs with clear-cut edges Stool
6 Fluffy pieces with ragged edges Stool
7 Watery, no solid pieces Stool

Etiology

Delayed bowel transit time is often cited as the cause of constipation, because the fecal contents remain in the large intestine for a longer time. This allows more of the water in the stool to absorbed, resulting in a hard, dry stool that is difficult to pass.

However, this begs the question of why the bowel transit time is delayed. Many factors may combine to produce constipation, including the following:

  • Inadequate fiber intake (recommended 20 - 35 g/day)
  • Inadequate fluid intake (recommended 64oz/day, more or less depending on climate and activity).
  • Inadequate exercise.
  • Ignoring or suppressing urge to defecate. This may be a self-perpetuating cycle - constipation may produce painful defecation, to which the patient responds by suppressing the call to stool. Other reasons for ignoring the call to stool may include distaste for the available facilities, or being too busy.
  • Training: cases have been reported in which it appears that the gut can be trained to follow a habitual schedule independent of eating schedule.
  • Stress: sympathetic fight-or-flight arousal suppresses intestinal activity.
  • Mechanical obstruction (tumor, congenital, adhesions, or impaction).
  • Disruption of nerve supply to the colon: multiple sclerosis, spinal nerve impingement, Parkinson's disease, stroke, diabetes, Hirschsprung's disease, iatrogenic (surgical).
  • Excessive anal sphincter tone.
  • Laxative or enema abuse leading to dependence.
  • Pregnancy (hormonal or due to compression of intestines by the gravid uterus).
  • Drugs that reduce peristalsis: opiate pain relievers, antidepressants, anticonvulsants, antispasmodics (muscle relaxants).
  • Drugs that promote water loss: diuretics.
  • Iron supplements, aluminum-containing antacids.
  • Lupus, scleroderma, uremia, amyloidosis.
  • Diverticulosis.
  • Constipation in children may be due to any of the above factors, but may also be a consequence of the potty training process, in which the child either lacks confidence to potty in the absence of a parent or associates pottying with negative experiences (Freud calls this anal-retentive behavior, and has developed elaborate psychological theories based on this process).
  • The elderly tend to be constipated, but it is not clear whether this is a normal part of aging, or a consequence of the above factors.

Diagnosis

In most cases, the cause of constipation can be determined by a careful case history and physical examination. Alarm signs such as blood in stools, recent changes in bowel movements, or weight loss merit particularly close scrutiny.

Bowel transit studies using a marker such as activated charcoal are simple and effective; while referral for more sophisticated X-ray studies using radio-opaque markers may reveal more detailed information.

Digital rectal exam can be used to assess anal sphincter tone, while referral for more sophisticated anorectal manometry can be used to evaluate anal sphincter muscle function, and can be used to evaluate a recommendation for biofeedback training.

Sigmoidoscopy can be used to examine the rectum and lower colon (sigmoid colon). The night before a sigmoidoscopy, the patient usually has a liquid dinner and takes an enema in the early morning. A light breakfast and a cleansing enema an hour before the test may also be necessary. Depending on the age of the patient and the level of suspicion, a referral for a complete colonoscopy may be indicated.

Referral for barium enema X-ray study may be indicated in cases with alarm signs.

Referral for defecography (an X-ray study of the defecation process) may be needed to assess anorectal dysfunction.


Differential Diagnosis


Treatment

  • Spinal manipulation by a Chiropractor, Naturopathic Medical Doctor, or Doctor of Osteopathy
  • Acupuncture: Sp-15, TB-6, St-25, St-37.
  • Increase fiber and fluid intake.
  • Increase exercise.
  • Laxatives:
    • Bulk-forming (fiber): A variety of over the counter preparations are available. Ensure adequate fluid intake or else these products may be counterproductive (form concrete-like impactions). E.g. Metamucil, Citrucel, Konsyl, and Serutan.
    • Stimulating: Increases peristalsis. E.g. phenolphthalein, Ex-Lax, Correctol, Dulcolax, Purge, Feen-A-Mint, and Senokot. (Phenolphthalein may be associated with increased cancer risk).
    • Stool softeners: E.g. Colace, Dialose, and Surfak.
    • Lubricating: E.g. mineral oil.
    • Osmotic agents: E.g. Milk of Magnesia, Citrate of Magnesia, Haley's M-O, Epsom salt in water (may cause severe cramping).
    • Purgatives: E.g. castor oil (may cause severe cramping).
    Note: use of laxatives is contraindicated if mechanical obstruction cannot be ruled out. Laxatives can be dangerous to children and should be given only with a doctor's approval.
  • Treat hypothyroidism
  • Treat underlying systemic diseases.
  • Modify drug therapy protocol or eliminate drugs by resolving underlying diseases being treated.
  • Stress reduction.

Prevention

  • Increase fiber and fluid intake.
  • Increase exercise.
  • Heed the call to stool.

Sequelae

  • Delayed emptying of the waste products in the intestines can lead to increased reabsorption of toxins that the liver eliminated from the blood.
  • Straining to expel hard stool may cause hemorrhoids.
  • Expelling hard stool may tear the skin of the anus, resulting in anal fissures.

ICD-9 Codes

ICD-9 CodeDescriptionComments
564.0Constipation 
560.30Fecal impaction 

References