Refer to surgeons if the assessment suggests bowel obstruction (clinical evidence e.g. abdominal exam + hernial orifices +/- abdominal X-ray). Avoid stimulants. Once obstruction ruled out then consider lactulose.
- There are criteria for an academic diagnosis of constipation Rome IV here
- In most patients constipation is not uncommon and needs a healthy diet with sufficient hydration, fibre and mobility to encourage a normal bowel habit and frequency. Some people for them normal is twice a day and others twice a week.
- NICE recommends a person's diet should contain whole grains, fruits (and their juices) high in sorbitol, and vegetables. Sorbitol from apples, apricots, grapes (and raisins), peaches, pears, plums (and prunes), raspberries, and strawberries.
- Fibre intake should be increased gradually (to minimize flatulence and bloating) adults should aim to consume 30 g of fibre per day. Advise the person that the beneficial effects of increasing dietary fibre may take several weeks.
- Straining For >1/4 (25%) of defecations
- Lumpy or hard stools: Form 1 of 2 on the Bristol Stool Form Scale; for > 1/4 (25%) of defecations
- Sensation of incomplete evacuation
For >1/4 (25%) of defecations
- Sensation of anorectal obstruction/blockage
For >1/4 (25%) of defecations
- Manual maneuvers to facilitate defecation
E.g. digital evacuation, pelvic floor support; for > 1/4 (25%) of defecations
- < 3 spontaneous bowel movements per week
Red flags for further investigations
- PR bleeding, weight loss, family history of colorectal cancer
- Tenesmus, anorexia, melaena, fevers night sweats, raised inflammatory markers
- Abdominal pain and distension, mass on PR
Advice on toileting routines
- Advise on a regular, unhurried toilet routine, giving time to ensure that defecation is complete.
- Advise on responding immediately to the sensation of needing to defecate.
- Ensure that people with limited mobility have appropriate help to access the toilet and adequate privacy.
- Ensure the person has access to supported seating if they are unsteady on the toilet.
- Common causes of new constipation are dehydration, immobility, opiates and codeine.
- In older persons a change in bowel habit may be a sign of potential colorectal disease and malignancy.
- Dehydration is also seen in older patients with poor oral intake or on diuretics.
- Significant new constipation needs a PR to see if there is retained hard stool that needs to be cleared out before a new bowel regimen. Also may feel a rectal mass.
- Assess with the team whether the patient requires further investigations
Associations with constipation
- Childhood: cystic fibrosis and Hirschsprungs
- Hypothyroid, Parkinson's Disease
- Colon cancer, Diabetes, Diverticulitis, haemorrhoids
- Irritable bowel syndrome (IBS)
- Multiple sclerosis, Pregnancy, Spinal cord disease
- Acute illness with immobility dehydration and reduced intake
- Opiates, antidepressants, diuretics, and antacids (calcium/aluminium)
- Anticholinergics, Calcium channel blockers, Iron, NSAIDS
Pharmacology: Drugs + Hydrate + Fibre in diet + mobilise/exercise
- Osmotic laxative (hard stool) bulks up stool with water an stimulates peristalsis and may cause abdominal distention and flatulence
- Macrogol e.g. Movicol half to one sachet od tends to be used when other strategies such as senna/lactulose have failed
- Lactulose e.g Lactulose 10 mls bd
- Phosphate and sodium citrate enemas as needed. Prescribe One Phosphate enema PR
- Stimulant laxative (soft stool slow to pass) stimulates nerves in colon and rectum
- Senna: hydrolyzed to the active metabolite by bacterial enzymes in the large bowel. Rx Senna One tablet BD for short term
- Bisacodyl 5-10 mg OD
- (picolax) Sodium Picosulfate 5-10 mg OD
- Sodium Docusate 500 mg OD: a surface-wetting agent which reduces the surface tension of the stool, allowing water to penetrate and soften it. Also has a relatively weak stimulant effect.
- Bulk forming : increases water content of stool and increasing faecal mass, stimulating peristalsis; also softens stools.
- Ispaghula husk e.g. Fybogel One sachet BD given in water preferably taken after food, morning and evening.
- Methylcellulose 3 tablets twice daily.
- Sterculia sachets 1-2 times a day, alternatively, one to two heaped 5-mL spoonfuls once or twice a day; washed down without chewing with plenty of liquid after meals
- Prokinetic laxatives
- Prucalopride: a selective, high-affinity, serotonin (5HT4) receptor agonist, which stimulates intestinal motility.
- Secretory laxatives
Lubiprostone: a chloride-channel activator which acts locally to increase intestinal fluid secretion and improve colon transit.
- Do not prescribe laxatives if there is suspected
- Intestinal obstruction or perforation.
- Paralytic ileus.
- Colonic atony or faecal impaction (bulk-forming laxatives).
- Crohn's disease or ulcerative colitis.
- Toxic megacolon.
- Severe dehydration (bisacodyl).
- Galactosaemia (lactulose).
- History of hypersensitivity to peanuts (arachis oil enema).
- Prescribe laxatives with caution if there is:
- Dehydration , secondary hypokalaemia
- Prolonged over usage or abuse
- Ischaemic heart disease or arrhythmias (prucalopride).
- Movicol is considered high in sodium, this should be taken into account for those people on a low salt diet.
Types of Treatment
- Offer a bulk-forming laxative first-line, such as ispaghula. Note: it is important for the person to drink an adequate fluid intake.
- If stools remain hard or difficult to pass, add or switch to an osmotic laxative, such as a macrogol. If a macrogol is ineffective or not tolerated, offer treatment with lactulose second-line.
- If stools are soft but difficult to pass, or there is a sensation of inadequate emptying, add a stimulant laxative.
- If the person has opioid-induced constipation:
Do not prescribe bulk-forming laxatives. Offer an osmotic laxative and a stimulant laxative (or docusate is an alternative which also has stool-softening properties).
- Advise the person to gradually reduce and stop laxatives once the person is producing soft, formed stool without straining at least three times per week.
- Opioid-induced constipation: avoid bulk-forming laxatives. Consider lactulose and a stimulant laxative (docusate)
- Disimpaction of stool: consider the following escalation choices
- Microlax enema
- Phosphate enema
- Arachis oil enema
- Manual disimpaction (with care)
- General Constipation
- Osmotic laxative: Movicol 1-2 sachets OD OR Lactulose 10 mg BD
- Add Stimulant: Senna or Docusate