• Constipation is defecation that is unsatisfactory because of infrequent stools, difficult stool passage, or seemingly incomplete defecation. Stools are often dry and hard, and may be abnormally large or abnormally small.

• Clarify what the person understands by their constipation.
• Assess the presence and degree of faecal loading/impaction and faecal incontinence.
• Assess the severity and impact of the constipation and any faecal incontinence.
• Assess the role of predisposing factors.
• Identify any organic causes of constipation.
• Assess effectiveness of management to date.
• Be alert for any 'red flags' that might indicate a serious underlying condition. Is there:
• Persistent unexplained change in bowel habits?
• Palpable mass in the lower right abdomen or the pelvis?
• Persistent rectal bleeding without anal symptoms?
• Narrowing of stool calibre?
• Family history of colon cancer, or inflammatory bowel disease?
• Unexplained weight loss, iron deficiency anaemia, fever, or nocturnal symptoms?
• Severe, persistent constipation that is unresponsive to treatment?

In depth

• No investigations are routinely required in an adult with constipation.
• However, if a secondary cause is suspected, special investigations might be required.

In depth

• Refer for suspected cancer if 'red flags' are present.
• Consider surgical referral when there is pain and bleeding on defecation (e.g. from an anal fissure) that is severe or does not respond to treatment for constipation.
• Refer for assessment by a specialist with an interest in constipation when:
• An underlying cause is suspected.
• Treatment is unsuccessful.
• Management may require further tests.
• Assessment is required prior to referral for other interventions (such as psychology, psychiatry).
• Consider referral to a Continence Service (when available) if faecal incontinence is a problem.
• Consider dietetics referral for more detailed support of diet.

In depth

• Bulk-forming: ispaghula husk, methylcellulose, sterculia and frangula
• Osmotic: lactulose and macrogols (polyethylene glycols)
• Stimulant: bisacodyl, senna and sodium picosulfate

In depth

• Adjust any constipating medication, if possible.
• Advise the person about increasing dietary fibre, drinking an adequate fluid intake, and exercise.
• Offer oral laxatives if dietary measures are ineffective, or while waiting for them to take effect.
• Start treatment with a bulk-forming laxative (adequate fluid intake is important).
• If stools remain hard, add or switch to an osmotic laxative.
• If stools are soft but the person still finds them difficult to pass or complains of inadequate emptying, add a stimulant laxative.
• Advise the person that laxatives can be stopped once the stools become soft and easily passed again.

In depth

• Begin by relieving faecal loading/impaction, if present.
• Set realistic expectations for the results of treatment of chronic constipation.
• Advise people about lifestyle measures — increasing dietary fibre (including the importance of regular meals), drinking an adequate fluid intake, and exercise.
• Adjust any constipating medication, if possible.
• Exclude underlying causes (e.g. hypothyroidism, metabolic disease, anal fissure, haemorrhoids).
• Laxatives are recommended:
• If lifestyle measures are insufficient, or whilst waiting for them to take effect.
• For people taking a constipating drug that cannot be stopped.
• For people with other secondary causes of constipation.
• As 'rescue' medicines for episodes of faecal loading.
• Laxatives are used as in short-duration constipation.
• Adjust the dose, choice, and combination of laxative to produce comfortable defecation with soft, formed stools once or twice a day.

In depth

• For hard stools, consider using a high dose of an oral macrogol (licensed for use in faecal loading/impaction).
• For soft stools or, for hard stools, after a few days treatment with a macrogol, consider starting or adding an oral stimulant laxative.
• If the response to oral laxatives is insufficient or not fast enough, consider:
• Using a suppository: bisacodyl for soft stools; glycerol alone or glycerol plus bisacodyl for hard stools.
• Using a mini enema — docusate (softener and weak stimulant) or sodium citrate (osmotic).
• If the response is still insufficient:
• Consider using a sodium phosphate or arachis oil retention enema (place high if the rectum is empty but the colon is full).
• For hard faeces it can be helpful to give the arachis oil enema overnight before giving a sodium phosphate (large volume) or sodium citrate (small volume) enema the next day.
• Enemas may need to be repeated several times to clear hard impacted faeces.
• The choice depends on individual preference and what has previously been tried.
• Regular use of a laxative may be needed after the faecal loading/impaction has been cleared.

In depth

• Laxatives can be slowly withdrawn when regular bowel movements occur without difficulty.
• Laxative medication should not be suddenly stopped.
• If a combination of laxatives has been used, reduce and stop one laxative at a time. Begin by reducing stimulant laxatives, increasing the dose of the osmotic laxative if necessary.
• It can take several months to be successfully weaned off all laxatives.
• Relapses are common and should be treated early with increased doses of laxatives.
• Laxatives need to be continued long term for:
• People taking a constipating drug that cannot be stopped.
• People with a medical cause of constipation.

In depth

• Defecation should be unhurried, with enough time to ensure that defecation is complete.
• Attempt defecation first thing in the morning, or about 30 minutes after a meal — this requires planning and time management.
• Respond immediately to the sensation of needing to defecate — people with limited mobility should have help to get to the toilet whenever they need to go.
• Supported seating can help if the person is unsteady on the toilet.
• Inadequate privacy can contribute to constipation.

In depth

• In general, the diet should be balanced and contain whole grains, fruits, and vegetables.
• Fibre intake should be increased gradually (to minimize flatulence and bloating) and maintained for life.
• Adults should aim to consume 18–30 g fibre per day.
• Although the effects of a high fibre diet may be seen in a few days, it may take as long as 4 weeks.
• Adequate fluid intake is important (particularly with a high fibre diet or fibre supplements), but can be difficult for some people (e.g. frail or elderly).
• Fruits high in fibre and sorbitol (e.g. apricots and prunes) and fruit juices high in sorbitol can help prevent and treat constipation.

In depth