All About Constipation – Dr Desmond Wai, Gastroenterologist

The Pooping Business in Singapore

Constipation is one of the commonest digestive complaints in Singapore. Generally speaking, constipation is defined as passing stools less than 3x per week, needing to strain to pass motion, passing hard and lumpy stools, feeling of incomplete defecation or requiring manual maneuvering to defecate. In layman term, constipation merely means passing motion with difficulty or less frequently.

Constipation was estimated to be about 25% among the general public in Singapore. Constipation is usually chronic, i.e., occurring for more than 12 weeks. We doctors are particularly concern about acute constipation, i.e. a recent change in bowel habit, as it may signify serious illness. We are equally concerned about chronic constipation as it can affect a person’s well-being and quality of life.

Causes of Constipation

Constipation can be caused by something blocking the lumen of the colon. Causes could involve a kink in the intestine, a cancer blocking the lumen, or a narrowing caused by previous intestinal injury. This is a serious concern as relief of the intestinal blockage is important. A blocked intestine can cause the abdomen to be distended, causes vomiting, as well as infection.

Constipation Ahead Toilet Sign

Constipation can also be caused by slow colonic transit, i.e., the intestines moving slowly to evacuate the feces. This, in turn, can be caused by many causes, like old age, neurological diseases like previous stroke or Parkinson’s disease, prolonged immobility, or abuse of laxatives.

Poor dietary habit can also be responsible. We need adequate fluid intake and fiber intake to form adequate stools. In people who do not consume enough water or fibre, they may have constipation as well.

Rarely, constipation can be caused by psychological stress, salt imbalances in the body, or other metabolic illnesses.

Finally, certain medications can cause constipation. Certain antidepressants, cough mixtures, pain killers, antacids, hypertensive medications, etc.

Evaluation of Constipation

Doctor's Stethoscope

When I see a patient with constipation, I would discuss to see if the person is having acute or chronic constipation, I will go through a list of questions to look for any secondary causes. Being in practice for 20 years, I would say most constipation are caused by benign causes like slow transit, irritable bowel syndrome, poor dietary habit, or medication (especially cough mixtures). But I have also seen many other serious causes like a narrowing in colon, cancer of the colon or hormonal causes.

It is recommended patients seek medical opinion if their constipation occurs recently, or if their constipation is impairing their quality of life.

Excluding Serious Causes Is Of Utmost Importance

The most important aspect in management is to ensure there are no serious causes, like colon cancer, hormonal imbalance, narrowing, etc., as these causes would require individualised treatment. Further investigations like blood tests, imaging and maybe endoscopies are often required.

An Apple A Day Keeps Constipation Away

An Apple A Day Keeps Constipation Away

Once serious causes are excluded by investigations, treatment would focus on relief of constipation.

One important aspect is adequate fluid intake, and adequate fibre intake. We recommend the general public to consumer 25-30 grams of fibre a day. Besides fruits and vegetables, people can also consume cereals, dried beans and whole grain bread to obtain additional fibre. One medium sized apple contains about 5-6 grams of fibre. Having 2 fruits like an apple and an orange a day, with vegetables during both lunch and dinner, would be sufficient for most people.


Medicine Capsules & Tablets

Medications can be classified into a few categories:

  • Extra fibres – they act as bulking agent to increase amount of stools
  • Stool softeners – they act by keeping water content within the lumen of the colon, thus helping the stools move in the intestines
  • Prokinetics – they are medications that make the intestines move faster. As they are prescription medication, patients have to consult their doctor before being prescribed.


Caution Stripes

Some over-the-counter constipation medications are actually stimulants to the colon. While they may help constipation, they can cause the colon to be “addicted” to the stimulants and the colon may become “lazy” when the stimulants are stopped.Though most of the constipation cases are due to irritable bowel syndrome with slow transit time and are benign in nature, some constipation can be caused by serious illnesses like cancer or stricture. In patients with alarming symptoms like weight loss, recent change of bowel habit, family history of colon cancer, passing black-coloured stools, etc., they should consult a doctor for further evaluation.

(Article reproduced with permission)

Dr Desmond Wai


About Dr Desmond Wai
MBBS, MRCP (UK), MMED (Internal Medicine)

Dr Wai runs his own practice, Desmond Wai Liver & Gastrointestinal Diseases Centre, at Mount Elizabeth Novena Specialist Centre. As a gastroenterologist, he has a special interest in liver diseases. Follow him on Facebook (doc.d.wai) to learn more of gastroenterology and his practice.