Constipation is a very common gastrointestinal disorder experienced by most people at some time during their lives. Constipation basically refers to a reduction in the frequency of bowel motions or increased difficulty passing stools. Numerous conditions can lead to constipation by disrupting the normal process of absorption, stool formation and propelling of feces within the large intestine. Fortunately most causes will not be anything serious and may be just due to a poor diet with insufficient fibre, poor fluid intake or a side effect of certain medications. However, some cases of constipation may be due to a serious problem such as colon cancer. Therefore if you experience severe or recurrent constipation it is important to see your doctor. They can advise you of appropriate lifestyle measures to reduce constipation and offer you medications (called laxatives) to help improve your bowel function if you require them.
Constipation is a symptom rather than a disease. There is no strict definition of constipation as normal bowel function varies so widely between different people. In general however it is defined as passage of stools less than 3 times per week or difficulty and pain during the passage of stools. However, it can be completely normal for breastfeeding babies to go a week without passing a bowel motion. A change in bowel function from what you perceive to be normal is therefore perhaps more important to highlight the diagnosis. During constipation it is common for stools to become small in size, hard, dry and difficult to pass out the body. Constipation is a really common symptom and can affect up to one in five people. Around 2% of the population suffers recurrent and constant constipation however most people will experience a mild form at some time during their life. Elderly people have high rates of constipation due to changes in diet, medications and decreased mobility and motility. If constipation goes unnoticed some severe side effects can occur such as haemorrhoids and damage or tearing of the anus.
Constipation occurs when the large intestine absorbs too much water from the stool to make it dry and hard or the bowel walls cannot contract adequately to pass the stool and waste products along fast enough. There are numerous causes of constipation some of which are listed below:
- Poor diet- Insufficient fibre and inadequate fluid intake are some of the most common causes of constipation.
- Life changes- Pregnancy, aging, stress and travel can all predispose to constipation..
- Irritable bowel syndrome.
- Metabolic disorders- Hypothyroidism, diabetes mellitus, hypercalcaemia and porphyrias can disrupt the function of the bowel.
- Drugs- Pain medications, blood pressure medications, anti-depressants and iron supplements have been associated with constipation. You may also experience constipation following surgery.
- Ignoring the urge to defecate.
- Gastrointestinal disorders- Obstruction of the bowel and other disease of the intestine or anus can interfere with the movement of stools.
- Damge to the nerve supply of the bowel secondary to spinal or pelvic injury or stroke
- Children often experience constipation as they hold back bowel movements or forget to go to the toilet.
The potential causes of constipation are thus extensive. In most cases constipation will be caused by factors that slow down the bowel such as inadequate fluid intake, low-fibre diet, lack of physical activity, inattention to bowel habits or medications. Rarely however it may reflect a serious underlying condition such as colorectal cancer. Therefore it is important that recurrent or severe cases of constipation are assessed by a doctor.
- Passage of hard stools infrequently.
- Abdominal pain or bloating.
- Straining during passage of bowel motions.
- Nausea, headacheand malaise (general feeling of discomfort) may be associated with constipation.
Your doctor will ask you lots of questions about the timing of your constipation and specific features of the stool to help them decide on the likely cause. They will also get you to describe you diet and any other general medical problems. The doctor will also want to check what medications you are taking as they may be the cause of your constipation. Next they will conduct a physical exam mainly focusing on the abdomen, pelvis and rectum. A rectal examination involves the doctor gently putting a gloved finger into the back passage to feel any masses or abnormalities and identify the presence of blood. You may require further investigations such as blood tests, stool samples, sigmoidoscopy, colonoscopy or barium enema to identify the cause of your constipation. These investigations are particularly important if your over 50, have lost weight, have blood in your stools or have a family history of colon cancer as you may be at risk of more sinister conditions.
Treatment of constipation largely focuses on treating the underlying cause. You can take several measures to help treat your problem including:
- Eating plenty of fibre (20-35 grams daily) which is found in cereals and fruit especially. You can talk to a dietician about the best way to increase your fibre intake. Some patients can benefit from fibre supplements such as Metamucil but these can have significant side effects such as cramping and gas..
- Drinking plenty of fluid.
- Exercising regularly.
- Responding to your body when it tells you it needs to defecate. Holding on excessively damages and weakens the bowel
If you employ these lifestyle measures you may be able to prevent constipation developing in the first place! If you have severe constipation and the above measures do not help, your doctor may prescribe you some laxative medications to help get the bowel moving. Several different types are available such as bulking agents, stool softeners, osmotic agents (that drag fluid into the stool), motility stimulants and lubricants. Your doctor will decide the type suitable for you based on the likely underlying cause. Laxatives should only be used for short periods because they can cause severe damage and lead to ‘lazy bowel syndrome’ where your bowel becomes reliant on them to function properly.
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