Bulk Forming

Useful first-line choice in adults when it is difficult to get adequate dietary fibre; better tolerated than bran. They are of particular value in adults with small hard stools if fibre cannot be increased in the diet. Usually avoided in opioid induced constipation. Chronic constipation started with bulk forming and in children first line

Must not be taken immediately before bed. Adequate fluid intake is important to reduce the risk of intestinal obstruction. Short constipation, use BF and if stools remain hard, add or switch to an osmotic laxative, soft but difficult to pass add a stimulant

Sterculia: Not to be taken with other constipating drugs

Osmotic

Lactulose: If used alone in opioid-induced constipation, it often needs to be given in large doses that cause bloating and colic. Sweet and sickly.Alternative to macrogol for chronic constipation. Add stimulant if no responce

Macrogols: Difficult to drink in prescribed volumes, Idrloax no electrolytes and Movicol-Half contains half the dose and electrolytes of Movicol

Softeners

Docusate: Probably acts both as a softening agent and a stimulant. May be a useful alternative for people who find it hard to increase their fluid intake.

Stimulant laxatives

Usually taken in the evening to produce a bowel movement the following morning.

Do not give in intestinal obstruction

Senna: Licensed only for short-term use. Syrup is unpalatable. Aged dosing: 12 and above 15mg, 6-12 years 7.5mg

Sodium picosulphate: Licensed only for short-term use. Syrup is palatable

Bisacodyl: Licensed only for short-term use. No syrup available.

The use of co-danthramer and co-danthrusate is limited to constipation in terminally ill patients because of potential carcinogenicity (based on animal studies) and evidence of genotoxicity. Avoid taking antacids and milk at the same time because the coating can be broken down

Rectal

 If the response to oral laxatives is inadequate, for soft stools consider rectal administration of bisacodyl, and for hard stools rectal administration of glycerol alone, or glycerol plus bisacodyl. Alternatively, a docusate sodium or sodium citrate enema may be tried. For hard faeces it can be helpful to give the arachis oil enema overnight before

Prucalopride

If at least two laxatives (from different classes) have been tried at the highest tolerated recommended doses for at least 6 months, the use of prucalopride (in women only) should be considered. If treatment with prucalopride is not effective after 4 weeks, the patient should be re-examined and the benefit of continuing treatment reconsidered.