Anti-diarrhoeals

Question 1

Class of anti-diarrhoeals

Answer 1

OK, BB Sorry Lah:
Opioid agonist, Kaolin/Pectin, Bismuth compounds, Bile salts-binding resin, Somatostatin-like peptides, Lyophilizate of killed Lactobacillus acidophilus

Question 2

Opioid agonist

Answer 2

Loperamide, diphenoxylate

Question 3

MoA of opioid agonists

Answer 3

Act on ENS to increase transit time

Question 4

SE of opioid agonists

Answer 4

Mainly CNS — addiction, abuse potential
However, loperamide does not cross BBB and is hence safer.
Diphenoxylate can cause CNS effect at higher doses and risk of dependence with LT use

Question 5

How to discourage abuse of diphenoxylate

Answer 5

Take with atropine — cause anticholinergic effects such as dry mouth, BoV
Atropine also contribute to anti-diarrhoeal effect

Question 6

Bismuth compounds

Answer 6

Bismuth subsalicylate, bismuth subcitrate potassium

Question 7

MoA of bismuth compounds

Answer 7

Not exactly known, however, there is degree of anti-microbial effect (absorb enterotoxin), hence commonly used for Tx of traveller’s diarrhoea
Subsalicylate also inhibits PG production, Cl secretion –> decrease stool frequency & liquidity

Question 8

SE of bismuth compounds

Answer 8

Generally safe profile.
Some side effects include harmless blackening of tongue, darkening of stools
Prolonged use may cause bismuth toxicity –> encephalopathy (h/a, confusion, seizures)
Salicyclate toxicity with high-dose bismuth subsalicylate

Question 9

MoA of Kaolin, pectin

Answer 9

Absorb bacterial toxins, fluid –> decrease stool frequency, liquidity; useful in acute diarrhoea

Question 10

SE of kaolin/pectin

Answer 10

Minimal systemic effect as not absorbed into circulation
Main issue would be constipation
Can also interfere with other drugs by binding & inhibiting them —avoid use within 2h of each other

Question 11

Bile salt-binding resin

Answer 11

Cholestyramine

Question 12

MoA of cholestyramine

Answer 12

Binds to bile salts –> alleviate diarrhoea caused by colonic secretory diarrhoea (e.g. Crohn’s, surgical resection –> malabsorption of bile salts –> diarrhoea)

Question 13

SE of cholestyramine

Answer 13

Constipation, bloating, faecal impaction
Worsens fat malabsorption if already deficient
Inhibits absorption of other drugs —avoid within 2h

Question 14

Somatostatin-like peptides

Answer 14

Somatostatin (IV), octreotide (SQ)

Question 15

MoA of SLP

Answer 15

Inhibit release of transmitters/hormones (gastrin) –> decrease GI motility, GB, intestinal & pancreatic secretions

Question 16

SE of SLP

Answer 16

Steatorrhoea, gallstones, fat-soluble vitamin deficiency

LT use a/w development hypothyroidism

Question 17

Use of SLP

Answer 17

Diarrhoea caused by GI neuroendocrine tumours (Carcinoid syndrome, VIP-oma), short bowel syndrome, gastric dumping syndrome, AIDS

Question 18

Lyopphilizate of killed lactobacillus acidophilus

Answer 18

Lacteol forte —for bacterial, TD

Question 19

MoA of lacteol forte

Answer 19

Adheres onto intestinal surface and normalize intestinal flora by competitive exclusion –> prevent over colonization of pathogenic organisms

Question 20

SE of lacteol forte

Answer 20

Minimal systemic effects as not absorbed

But maintain hydration

Question 21

Contraindication of Lacteol Forte

Answer 21

Individuals with lactose intolerance as it is a component of the drug