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University Surgical Cluster

Common Conditions:

Benign Prostatic Hyperplasia (BPH)

Irritable Bowel Syndrome

Breast Surgery

Kidney Stones

Colon Cancer


Erectile Dysfunction

Prostate Cancer

Face Lift

Upper Gastrointestinal Surgery


Urinary Incontinence


What is constipation?


Constipation is a symptom that has different meanings to different people. These include:


  • Infrequent bowel movements
  • Decrease in the volume or weight of stool
  • The need to strain to have a movement
  • A sense of incomplete evacuation
  • The need for enemas, suppositories or laxatives in order to maintain regularity


What is normal bowel habits?


This varies from person to person and can be affected by diet.


Like how height varies from person to person, bowel habits are different for different people. For most people, it is normal for bowel movements to occur from three times a day to three times a week; other people may go a week or more without experiencing discomfort or harmful effects.


Normal bowel habits are affected by diet. The average diet includes 12 to 15 grams of fiber per day, although 25 to 30 grams of fiber and about 60 to 80 ounces of fluid daily are recommended for proper bowel function. Exercise is also beneficial to proper function of the colon.


About 80 percent of people suffer from constipation at some time during their lives and brief periods of constipation are normal. Constipation may be diagnosed if bowel movements occur fewer than three times weekly on an ongoing basis.


What causes constipation?


There are many causes of constipation. These include mechanical causes (structural blockage in the colon), functional causes (no structural blockage in the colon, just a result of how the colon moves) and medical reasons. The most worrisome cause to look out for is cancer.


  • Anatomic causes
    • CANCER
    • Stricture (Narrowing)
  • Functional causes
    • Irritable bowel syndrome
    • Slow transit constipation
    • Pelvic outlet dysfunction
  • Medical causes
    • Medication
    • Disorders of nervous system
      • Parkinson's disease
      • Stroke
      • Spinal cord injuries
    • Disorders of endocrine system
      • Thyroid disease


What factors affect constipation?


Excluding the worrisome causes of constipation, some factors in our lives can contribute to constipation. These include:


  • inadequate fiber and fluid intake
  • sedentary lifestyle
  • environmental changes
  • travel
  • pregnancy
  • change in diet
  • repeatedly ignoring the urge to have a bowel movement


Can medication cause constipation?


Yes. The following is a list of medication that can cause constipation. Remember to talk to your doctor about it, do not stop them on your own.


  • Pain killers
  • Antidepressants
  • Tranquilizers
  • Psychiatric medications
  • Blood pressure medication
  • Diuretics
  • Iron supplements
  • Calcium supplements
  • Aluminum containing antacids
  • Laxative dependence or abuse


When should I see a doctor about constipation?


As 80% of people can get temporary constipation that goes away, we recommend that you seek a doctor's advice if the change in bowel habit is persistent (more than 3 weeks) of if there are any warning signs.


  • Any persistent change (more than 3 weeks) in bowel habits
    • Increased frequency
    • Decreased frequency
    • Increased size of stool    
    • Decreased size of stool
    • Increased difficulty in evacuating
  • Warning signs
    • Blood in stools
    • Loss of weight
    • Loss of appetite


How can the cause of constipation be determined?


Remember the causes of constipation? Your doctor will try to exclude worrisome causes, like cancer (especially if you are older than 50 years). He may do a colonoscopy, a CT colonography or even a barium enema or some form of screening.


He will also go through your history to see if you have any medical conditions predisposing to constipation.


After excluding any mechanical cause of obstruction, and if your doctor tells you that you have functional constipation, he may evaluate you further to see if you have a slow-transit colon ('sleepy' colon) or pelvic floor dysfunction (discoordination of your pelvic floor and 'pooping' muscles) by ordering transit marker studies or defecography studies.


I have had a colonoscopy and my doctor told me my colon is normal, I still have constipation. What else can I do?


Simple measures can include increasing the fibre in your diet, drinking more water. Exercise is good as it stimulates the colon. Sometimes, if the doctor finds that you have incoordination of your 'pooping' muscles (pelvic floor dyssynergia), the physiotherapist can teach you exercises to retrain the muscles.


What is a slow transit colon?


Sometimes also known as a 'sleepy colon' or a 'lazy colon' or 'inactive colon', it essentially means that the colon moves slow and hence propels the stool in the colon slowly.


The colon is a muscular tube that connects the small intestines to the anus. It propels the stool that comes out of the small intestines towards the rectum and anus.


What is pelvic floor dyssynergia?


Also known as puborectalis paradoxis, non-relaxing puborectalis, pelvic floor dysfunction, it is a discoordination of the 'pooping' muscles. In essence, 'pooping' involves the coordination of several muscles. Your abdominal muscles need to contract and squeeze the stool out, and at the same time, your anal sphincter muscles need to relax and open up to let the stool out and your puborectalis needs to relax and let the kinked rectum straight up so that the stool can pass out easily. In pelvic floor dyssynergia, the puborectalis contracts even more and kinks the rectum further so the stool has more difficulty passing through. Physiotherapy exercises or biofeedback techniques can help you become more aware of the puborectalis, and you can learn to relax the puborectalis during the process of defecation (pooping).


What is the puborectalis?


The puborectalis is a muscle, which is part of the pelvic floor, which slings around the rectum and attaches to the pubic bone. Usually when we are doing our everyday stuff, the rectum is kept kinked but the puborectalis so that stool doesn't accidentally slip out. When it's time to have a bowel movement, the puborectalis is supposed to relax, let the rectum straighten out so that stool can pass out easily.


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