constipation & irritable bowel syndrome (IBS)

Question 1

Bulk forming laxatives

Answer 1

Wheat bran, psyllium husk, Ispaghula husk, semisynthetic cellulose – carboxy-methyl cellulose and
polycarbophils

Question 2

Osmotic laxatives

Answer 2

Eg: Lactulose, sorbitol

Question 3

Lubricant laxatives

Answer 3

Eg: Liquid paraffin

Question 4

Surfactant laxatives:

Answer 4

Eg: Dioctyl sodium sulfosuccinate (docusate sodium)

Question 5

Osmotic purgatives

Answer 5

a) Saline purgatives such as Magnesium sulfate, magnesium hydroxide, sodium sulfate, sodium phosphate;

b) Polyethylene glycol (PEG)

Question 6

Irritant purgatives

Answer 6

Anthraquinone group
Organic irritants
Oils

Question 7

Anthraquinone group

Answer 7

Senna, cascara, aloe

Question 8

Organic irritants

Answer 8

Phenolphthalein, bisacodyl, sodium picosulfate

Question 9

Oils

Answer 9

Castor oil, it is hydrolysed in intestine by pancreatic lipase to ricinolic acid which increases the intestinal motility, but no longer a favoured purgative because of its unpalatability, frequent cramping, after-constipation, and risk for damaging intestinal mucosa.

Question 10

In bedridden patients
To prevent constipation:

Answer 10

Psyllium
* Lactulose
* Liquid paraffin
* Docusates

Question 11

In bedridden patients
To treat constipation

Answer 11

• Bisacodyl
• Senna
• Soap-water enema or
  glycerine enema

Question 12

In functional constipation

Answer 12

• Dietary fiber
• Bisacodyl
• Senna

Question 13

In post-operative patients

Answer 13

• Psyllium
• Lactulose
• Docusates

Question 14

For bowel preparation

Answer 14

• Magnesium salts
• Senna

Question 15

IBS DRUGS

Answer 15

1. Antidiarrheal – Antispasmodic drugs
2. Antidepressants
3. 5-HT3 antagonists
4. Chloride channel activator
5. Miscellaneous

Question 16

Antidiarrheal – Antispasmodic drugs:

Answer 16

Loperamide, diphenoxylate, fedotozine, dicyclomine, hyoscyamine, mebeverine

Question 17

Antidepressants

Answer 17

Amitriptyline, desipramine

Question 18

5-HT3 antagonists:

Answer 18

Alosetron

Question 19

Chloride channel activator

Answer 19

Lubiprostone

Question 20

Miscellaneous

Answer 20

Clonidine, buspirone, CCK1 receptor antagonists (loxiglumide, dex-loxiglumide),
sumatriptan, selective inhibitors of peripheral μ receptors (methylnaltrexone, alvimopan)