Constipation

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About 10–20% of individuals believe that they suffer from constipation because their normal bowel habits are not occurring on a daily basis. It is thought that stooling should be ≥ 3 times per week. Less than 3 stooling times per week, is called constipation.

[edit] Patient groups at risk and possible causes

  • Elderly patients: due to sedentary lifestyle, poor mobility and decreased food and fluid intake
  • pregnant women: due to fetal pressure and increased progesterone levels, which cause a decrease in peristaltic movements
  • Lack of exercise and poor mobility
  • Medical causes: hormonal disturbance, neurogenic disorders ecc.
  • Dietary: Diets low in fibres and water
  • Drugs.: e.g. opioids, anticholinergic drugs, Iron, diuretics, antidepressants, antihistamines, antispasmodics, antidiarrhoeal agents, phenothiazines, and aluminum antacids.

[edit] Managing constipation

  • Increasing the amount of fibres
  • Increasing the amount of fluid
  • Avoiding drugs which induce constipation
  • Regular exercise
  • Using Laxatives; Medication should be considered when problems like hemorrhoids occur. In this case, stool must be made very watery to prevent bleeding.

[edit] Laxatives

Laxatives must not be used for a long-time otherwise atonia and dependence will be the rebound effects and peristalsis would become difficult


Laxatives can be divided in five main types:

  • Bulk-forming: These are polysaccharide and cellulose derivatives that are not digested. They increase fecal mass which stimulates peristalsis. e.g. ispaghula husk; It absorbs water, softens stool and promotes peristalsis.
  • Stool softener (emollients): Arachis oil enema and liquid paraffin are part of this type of laxatives. They work by coating and softening the faeces. The stool remains soft and the passage is made easier.
    These emollients can cause irritation, granulomatous reactions and interfere with the absorption of fat-soluble vitamins.
  • Surfactants lower the surface tension, facilitating the penetration of water into faeces to make it softer. Na+-docusate is the most famous emollient or stool softener.
  • Stimulants are irritants which try to increase peristalsis directly, probably through an effect on the myenteric nerve plexus. They decrease the absorption of water and electrolytes. Examples: Bisacodyl (ducolax) and senna, cascara and sodium picosulfate. Stimulant laxatives have a rapid onset of action (6–12 hours after oral administration and 15–30 minutes when administered rectally).
  • Osmotic laxatives include mannitol, lactulose, glycerin suppositories, sorbitol, and macrogol. They are poorly absorbed and so pull water into the lumen of the colon by increasing the osmolarity of stool.
Drugs for constipation (laxatives and Prokinetic agents)
Softeners, emollients Liquid paraffin
Contact laxatives Bisacodyl (Dulcolax)   Senna   Cascara   Sodium picosulfate
Bulk-forming laxatives Ispaghula
Osmotically acting laxatives Glycerin suppositories   Magnesium salts   Lactulose (Duphalac)   Macrogol   Mannitol   Sorbitol   Sodium phosphate
Prokinetic agents Clebopride   Prucalopride (Resolor)
Others (irritable bowel syndrome accompanied by constipation) Linaclotide (Constella, Linzess)