Constipation

Question 1

Bulk laxatives MOA

Answer 1

fibre replacement. They swell in the fluids by attracting water and form gels that promote healthy bowel movements.

Question 2

Bulk laxative drugs

Answer 2

ispaghula husk (fybogel)

Question 3

Dosing for ispaghula husk

Answer 3

1 sachet BD

Question 4

side effects of ispaghula husk

Answer 4

abdominal cramps, constipation

Question 5

counselling points for ispaghula husk

Answer 5

1. do not leave it to stand as it will solidify
2. should not be taken before going to bed
3. space apart 2 hours from other medications

Question 6

onset of action of ispaghula husk

Answer 6

12-72 hours

Question 7

Osmotic laxative drugs

Answer 7

• lactulose

- phospho-soda oral solution

Question 8

osmotic laxative MOA

Answer 8

draws water into colon causing distention and increasing motility

Question 9

Dosing for phospho-soda oral solution

Answer 9

PO 20ml OD dilute with 1/2 glass cold water then 1 full glass of cold water

Question 10

side effects of phospho-soda oral solution

Answer 10

• abdominal pain

- diarrhoea

Question 11

contraindications of phospho-soda oral solution

Answer 11

• renal problems

- heart failure

Question 12

counselling points for phospho-soda oral solution

Answer 12

• take 30min before meal or bedtime
• drink enough water
• if nothing happens 6 hours after 1st dose, take another dose

Question 13

onset of action of phospho-soda oral solution

Answer 13

30min to 3 hours

Question 14

Lactulose dosing

Answer 14

PO 15ml BD can increase to 30ml

Question 15

side effects of lactulose

Answer 15

abdominal cramps, flatulence, nausea and vomitting

Question 16

contraindication of lactulose

Answer 16

patients requiring low galactose diet

Question 17

counselling points for lactulose

Answer 17

• take with meals to reduce GI discomfort
• mix with juice, water, milk
• drink plenty of water
• suitable for diabetics

Question 18

onset of action of lactulose

Answer 18

24-48 hours

Question 19

Enema MOA

Answer 19

increases bulk volume and water content of stools

Question 20

Enema drugs

Answer 20

fleet enemas

Question 21

dosing for fleet enemas

Answer 21

PR 1 bottle

Question 22

side effects of fleet enema

Answer 22

abdominal cramps, local irritation

Question 23

contraindication of fleet enema

Answer 23

• severe kidney disease

Question 24

counselling points for fleet enema

Answer 24

1. counsel patient on how to administer enema

2. not for frequent use as it can cause trauma to rectum

Question 25

onset of action for fleet enema

Answer 25

2-5mins

Question 26

Lubricant laxatives Drug

Answer 26

liquid paraffin

Question 27

Liquid paraffin MOA

Answer 27

softens the faecal contents by coating them and preventing colonic absorption of water

Question 28

dosing of liquid paraffin

Answer 28

PO 10-30ml at night or when required

Question 29

side effects of liquid paraffin

Answer 29

- abdominal cramp - diarrhoea - nausea and vomitting - anal seepage of liquid paraffin

Question 30

contraindication for liquid paraffin

Answer 30

- pregnancy - children less than 6 - bedridden patients - elderly - patients who cannot swallow

Question 31

counselling points for liquid paraffin

Answer 31

- do not use for more than 1 week - do not administer with food or meals - prolonged administration can lead to decrease absorption of lipid-soluble vitamins (ADEK)

Question 32

onset of action of liquid paraffin

Answer 32

6-8 hours

Question 33

stimulant laxatives drugs

Answer 33

- bisacodyl | - senna/sennosides

Question 34

Biscodyl MOA

Answer 34

- produces contraction of the entire colon

Question 35

Senna/sennosides MOA

Answer 35

stimulates colonic motility

Question 36

Dosing for bisacodyl

Answer 36

5-15mg at night for tablets PR 10mg at night or suppository

Question 37

side effects of bisacodyl

Answer 37

abdominal cramps

Question 38

contraindications for bisacodyl

Answer 38

intestinal obstruction

Question 39

Counselling points for bisacodyl

Answer 39

- swallow tablet whole do not crush - do not administer within an hour of antacids or dairy products - should not be used for more than 1 week - counsel on administration of suppository

Question 40

Onset of action for bisacodyl

Answer 40

tabs: 6-12 hours suppository: 15-60mins

Question 41

Dosing for senna/sennosides

Answer 41

PO 2 tablets at night

Question 42

side effects for senna/sennosides

Answer 42

abdominal cramps

Question 43

Counselling points for senna/sennosides

Answer 43

- taken with or without food - administer 2 hours before or after other meds - urine may discolor to red or yellowish brown - should not be used for more than a week

Question 44

onset of action for senna/sennosides

Answer 44

6-12 hours

Question 45

which drug has the fastest onset of action?

Answer 45

phospho-soda oral solution with the onset of action of 30min - 3 hrs