Drug for constipation & diarrhoea

lecture on drugs for constipation & diarrhoea

1. DRUG FOR CONSTIPATION & dIARRHOEA - Dr. jerin 12:31 PM 1

2. constipation Definition : Infrequent or incomplete passage of hard feces; Any decrease from the normal bowel movement in an individual should be considered constipation. Causes : Dietary Old age Drug induced Malignancy 12:31 PM 2

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4. laxatives These are drugs that promote evacuation of bowels . Based on there intensity of action. Laxative or aperient : milder action, elimination of soft but formed stools. Purgative or cathartic : stronger action resulting in more fluid evacuation. Many drugs in low doses act as laxative and in larger doses as purgative. 12:31 PM 4

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6. Bulk laxatives Increase the volume & lower the viscosity of intestinal contents forming a large, soft, solid stool. It consists of indigestible vegetable fibre & hydrophilic colloids. Eg. Methylcellulose – Semisynthetic, colloidal hydrophilic derivative of cellulose Bran - residue left when flour is made from cereals Ispaghula husk Plantago seeds Bulk laxatives interfere with the absorption of other drugs. Should be avoided in patients with stenosis or adhesion of the gut. 12:31 PM 6

7. Uses : Functional constipation Conditions where straining is to be avoided – haemorrhoids, fissures Irritable bowel syndrome Useful also in diarrhoea – forming ‘solid’ to ‘formed’ stool. Lower plasma cholesterol level – dietary fibres like pectin bind to bile acid & prevent their absorption. 12:31 PM 7

8. stool softener Docusate sodium Anionic detergents. Softens the stool my lowering the surface tension of the intestinal content, thus retaining more water in the faeces. Requires 1-3 days Side effects Nausea, abdominal pain Unpalatable bitter taste Slow onset of action. 12:31 PM 8

9. Liquid paraffin Chemically inert mineral oil that is not digested. Lubricates & softens the faeces. Side effects Lipid pneumonia Malabsorption of vit A, D, E, K (fat soluble vitamins) 12:31 PM 9

10. Stimulant purgatives Phenolphthalein Litmus like indicator. Acts on the colon. Onset of action : 6-8hrs Side effects Allergic reactions Cardiac toxicity Not used now 12:31 PM 10

11. Bisacodyl Related to phenolphthalein. Converted to a active metabolite in intestines. Can be administered orally or as rectal suppositories. Acts on the colon. Side effects Prolonged use can cause proctitis. (not to be used longer than 10 days) 12:31 PM 11

12. Osmotic purgatives They are not absorbed in the intestine; osmotically retains water and increases the bulk of the intestinal content. They produce soft stools in 1-3hrs. Nonabsorbable salts (saline purgatives) Eg. Magnesium hydroxide, magnesium sulphate, sodium potassium tartrate(Rochelle’s salt), sodium sulphate, sodium phosphate. These are not used to treat constipation. Used for preparing bowel before surgery & colonoscopy . Also food/ drug poisoning. 12:31 PM 12

13. Lactulose Semisynthetic disaccharide. Not absorbed or digested and retains water. Broken down by colonic bacteria to osmotically more active products. Inhibits the absorption of ammonia – hence can be used for hepatic coma. Side effects Flatulence & flatus Cramps nausea 12:31 PM 13

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15. diarrhoea Definition Passage of more than 200g of daily & frequency of more than 3 bowel movements per day.(if consistency is liquid or semiformed , even one episode is considered diarrhoea) Also associated with urgency of defecation & faecal incontinence. Causes Infection Food poisoning Drug induced Malabsorption 12:31 PM 15

16. Classification 12:31 PM 16

17. adsorbents These compounds adsorbs intestinal toxins & micro organisms. They also interfere with other drug absorption. Its banned in India Eg. Kaolin, Pectin, Chalk, Activated charcoal 12:31 PM 17

18. absorbants These are colloidal bulk forming substance. They modify the consistency & frequency of stools they also reduce abdominal pain. Eg. Ispaghula, methyl cellulose, carboxy methyl cellulose 12:31 PM 18

19. Anti secretory Racecodotril Pro drug : active compound – thiorphan Thiorphan inhibits enzyme enkephalinase & prevents the degradation of enkephalins. (enkephalins are neurotransmitter in the gut that have antisecretory actions) Onset of action is quick. Not to be used for more than 7 days. 12:31 PM 19

20. Octreotide Synthetic analog of somatostatins Actions Reduces GI motility & fluid secretion Inhibits the secretion of various hormones like gastrin, secretin, cholecystokinin, growth hormone, insulin, glucagon, 5HT, pancreatic polypeptide & vasoactive intestinal peptides Uses Gastrointestinal secretory tumors causing diarrhoea Diarrhoea due to vagotomy Dumping syndrome 12:31 PM 20

21. Anti motility Loperamide Opiate with selective action GI tract. opioid receptor agonist Onset of action – 1-2hrs Duration of action 12-18hrs Contraindicated in children & infective diarrhoea Side effects Paralytic ileus, abdominal distention, toxic megacolon.   12:31 PM 21

22. Thank you…  12:31 PM 22