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Constipation Information

What are the symptoms of constipation?

Constipation is characterised by a difficulty in passing bowel motions; the motions are often less frequent than normal, and the stools themselves hard and difficult to pass.

Constipation can be identified by a reduction in the normal frequency of bowel movements, which will be different for everyone; there is a common misconception that constipation is present if there is not a bowel movement each day - however, there are many factors that influence how frequently this will happen, many of which are discussed below, and a normal range can be anything from 3 motions per day, to 3 per week.

What are the causes of constipation?

The bowel movement is the final stage in the digestion and processing of food. This starts in the stomach, and continues on through the small intestine and into the colon, or large intestine. It is here that the stools ('faeces') are formed; these are made up of the indigestible residue of the ingested food, plus bacteria, water, and some cells shed from the lining of the colon.

Fibre, or 'roughage', is an important part of the human diet even though it is not digestible material. Movement of the contents of the gut towards the rectum is achieved by the muscles in the walls of the intestine, which contract and relax in waves ('peristalsis').

This muscle activity is stimulated by the presence of material in the intestine. In the colon, the relatively bulky faeces stretch the walls of the colon triggering the peristaltic waves; as the faeces move slowly through the colon, water is continually absorbed, and the more slowly they move, the drier and harder they will become. A diet which is high in fibre will produce faeces that are bulkier, which will be moved easily by the colon; retaining some water means they remain softer and easier to pass without straining.

The amount of water absorbed in the colon is influenced by the total amount of fluid that has been consumed. A low fluid intake leads to more water being absorbed from the faeces, regardless of the speed at which it is moving; drinking plenty of water reduces this effect.

Dietary factors are important in constipation, but there are other possible causes: some drugs can reduce the muscle activity in the colon and cause constipation, including iron tablets, some anti-depressants, and certain painkillers (such as codeine or morphine). The general level of physical activity is also relevant; an inactive lifestyle leads to a reasonably inactive bowel. Increasing the level of exercise taken can help to stimulate the muscles in the colon, as well as elsewhere in the body.

What complications might occur?

The long-term complications of a low fibre diet, typical of many people today, can be potentially serious. It is thought that the incidence of bowel cancers in the West, which is high in comparison to the population of less developed countries who have diets containing large amounts of fibre, is in part due to our low fibre diet.

Long-term constipation, with straining, could be a factor in the development of haemorrhoids in later life. Haemorrhoids are very common in Western countries, and much less common in countries where high fibre diets are consumed.

The over-use of laxatives can cause long-term problems. Some laxatives work by stimulating the bowel into action to increase the frequency of bowel movements, however the continued use of such medicines can cause the muscles in the wall of the colon to become lazy and can even lead to nerve damage; at the very least, a vicious circle will develop, where laxatives are continuously needed to promote a bowel movement.

Pronounced pain, and bloating of the abdomen accompanying constipation, are signs that need to be referred to your doctor immediately.

How can I treat constipation?

Relief from constipation can be obtained by modifying the diet, taking more exercise, or using non-prescription laxatives to restore normal bowel frequency.

Fibre plays an important role in stimulating the bowel; a simple and effective step to take in improving regularity is to eat more fibre in the diet. It is now quite common for people in developed countries to consume large amounts of refined and convenience foods, that have only a low level of fibre; fresh fruit, vegetables and wholemeal breads contain fibre and will help to regulate the bowels. They also contain important vitamins and trace elements, and will help to maintain general health.

Adequate fluid intake is also important. The more water you drink, the less need there is for your body to reabsorb from the bowel; ideally, your fluid intake per day should be approximately one and a half litres, most of which should be water - drinking plenty of water should certainly help ease constipation.

Exercise helps to stimulate the muscles in the colon, speeding up the passage of stools and preventing them from becoming too dehydrated; exercise is also generally beneficial to the body and will also improve your general health. There are many activities which can be considered as exercise - brisk walking, swimming, and even cutting the grass will benefit many body systems as well as the bowel. Taking exercise does not mean you have to spend time in a gym!

What treatments are available for me to purchase?

If changing your diet and taking more exercise do not appear to be improving the symptoms, a laxative may be of benefit. There are several types of laxatives available, which will be discussed in the next section; further advice on these products or your symptoms can be obtained from the Pharmacy2U pharmacist. What treatments are available for me to purchase? If a laxative is needed, there are several available for purchase without a prescription. Among the most common ingredients are the following:

Ispaghula is a bulk-forming laxative - it adds fibre to the stool to increase the size, and make it easier for the stool to pass through the bowel. It is a relatively mild laxative and is a good option to use first - it can also safely be used on a regular basis, as it passes straight through the bowel without being absorbed, and in fact is prescribed by doctors for long-term use in some bowel conditions. As bulk-forming laxatives are essentially fibre supplements, there may be a delay of a few days before they start to work. A popular example of this type of laxative is Fybogel.

Lactulose is classed as an osmotic laxative, which means that it works by holding more water in the faeces thus making them softer and easier to pass. It may take up to 48 hours to produce an effect but is also perfectly safe to use on a regular basis, as it is not absorbed by the body at all.

Senna and Bisacodyl 
These are stimulant laxatives, that work by speeding up the muscular contractions in the bowel. They work faster than the bulk-forming and the osmotic laxatives, and should be taken before going to bed to produce a bowel movement the following morning. These products are only recommended to be taken for a few days at the most; over-use can actually reduce the muscle contractions of the gut, making the constipation worse. Examples of these are Senna Tablets and Dulco-Lax.

Liquid Paraffin 
Liquid paraffin is classed as a lubricant laxative, or a faecal softener, and works purely by coating and softening the stool to make it easier to pass and preventing the further absorption of water by the colon. However, this is no longer recommended, as it can cause problems of its own - being oily in nature, some nutrients and vitamins from food are bound by it and are prevented from being absorbed by the body; it can cause a form of pneumonia if inhaled into the lungs; and leakage from the anus can occur. Other laxatives are safer and more effective.

For the full range of laxatives available from Pharmacy2U please click here

If advice is required on the most suitable laxative please click here to consult a Pharmacy2U pharmacist. 

What treatments are available from my doctor?

Most laxatives available on prescription are also available to buy and work in the same ways as the products discussed above; if you suffer from constipation which does not respond to the advice above, or to a short course of non-prescription laxatives, you should see your doctor.

What additional investigations might be needed?

If the constipation comes on suddenly, is accompanied by pain, abdominal distension or bleeding from the back passage, this may indicate a more serious problem, and should be seen by your doctor urgently. Investigations of the bowel may be undertaken, by X-rays or fibre-optic endoscopes, to identify any underlying problems which could be causing the symptoms.

Any other information I should have?

Constipation is a common problem in pregnancy, occurring in as many as one in three women; hormonal changes can cause this, and iron tablets which are commonly prescribed during pregnancy also have constipation as a potential side effect. It's important not to take stimulant laxatives in this situation; bulk-forming laxatives are safe to use, although they can cause some abdominal discomfort when used late in pregnancy. Your doctor will advise further if this becomes a problem.

Long-term constipation is a common problem in the elderly, for many reasons, including lack of exercise, avoidance of high-fibre foods which can be difficult to chew, and side effects from some medicines which they may be taking. Bulk-forming laxatives and osmotic laxatives are commonly prescribed to manage this problem; if you are not sure if a medicine you are taking can cause constipation, ask our pharmacist for more advice.

Constipation can be a very uncomfortable problem, which can usually be resolved quickly by modifying the diet, taking exercise, or using non-prescription medicines; it's important to understand that when it comes to the frequency of bowel movements, everyone is different, and just because you don't pass a stool every day, this does not necessarily mean that you are in need of any help. Stimulant laxatives are ideal to relieve constipation in the short term, but should not be used for more than a few days at a time; bulk-forming and osmotic laxatives are safe to take over a long period of time, however you should see your doctor if the problem persists, to ensure that any other underlying causes are ruled out.