Drugs for diarrhea Flashcards
Types of acute diarrhea drugs (4)
- opioid agonist
- intestinal adsorbents
- colloidal bismuth compounds
- lyophilizate
opioid agonist examples
LOPERAMIDE, diphenoxylate (+ atropine)
opioid agonist MOA
- act in enteric NS (mu + delta receptors) -> increase colonic transit time
opioid agonist adverse effects
- addiction for diphenoxylate
*loperamide does not cross BBB
why is diphenoxylate formulated with atropine
- discourage overdose by causing adverse effects (dry mouth etc)
- aid in antidiarrheal effect (parasympathetic slows GI motility)
first line for symptomatic control of diarrhea with unknown cause
LOPERAMIDE
intestinal adsorbents examples
DIOSMECTITE (Mg, Al silicate clay), kaolin (Mg Al silicate clay)
intestinal adsorbents MOA
- absorb bacteria, toxin, fluid -> decrease stool liquidity and number
- use in acute diarrhea (not chronic)
intestinal adsorbents adverse effects
- constipation
- can bind to other meds: DO NOT take within 2 HOURS of other medication
colloidal bismuth compounds examples
BISMUTH subcitrate, bismuth subsalicylate
bismuth compound MOA
- Bismuth has an antimicrobial effect and binds enterotoxins, which has benefit for treating traveller’s diarrhoea
Specifically bismuth subsalicylate:
Rapid dissociation in stomach allowing absorption of salicylate -> salicylate inhibits intestinal prostaglandin production and chloride secretion -> reduces stool frequency and liquidity in acute infectious diarrhoea
bismuth compound adverse effects
- prolong use cause bismuth toxicity (encephalopath(
- avoid in RENAL INSUFFICIENCY
- salicylate toxicity at high doses of bismuth subsalicylate
Lyophilizate of killed
Lactobacillus acidophilus example
LACTEOL FORT
lacteol fort MOA
– heat-inactivated Lactobacillus acidophilus
– Adheres onto the surface of intestinal cells and normalizes intestinal flora by competitive exclusion
– interfere with the intestinal adherence of other micro- organisms -> over colonization of these organisms is prevented
lacteol fort indication
traveler’s diarrhea
lacteol fort adverse effects
- little risk of adverse effects
- MAINTAIN HYDRATION
- contraindicated in LACTOSE INTOLERANT
drugs for chronic diarrhea (2)
- bile salt binding resins
- somatostatin-like peptides
bile salt binding resins example
cholestyramine
bile salt binding resin MOA
- Bile salts normally absorbed in the terminal ileum
– Disease of the ileum (e.g., Crohn’s disease) or surgical resection leads to malabsorption of bile salts resulting in colonic secretory diarrhoea (osmotic laxative-like effect of bile salt in colon)
– Bile salt-binding resins bind to bile salts alleviating diarrhoea caused by excess fecal bile salts
cholestyramine indication
diarrhea from diseases of ileum (Crohn’s disease) or surgical resection
cholestyramine adverse effects
- bloating, flatulence, constipation
- binds to other drugs, DO NOT give within 2 HOURS of other oral drugs
somatostatin-like peptides examples
OCTREOTIDE (subcutaneous/ IV)
octreotide MOA
– Mimics somatostatin hormone released in the GI tract, pancreas and hypothalamus in the brain
physiological effects including:
- Inhibition of release of various transmitters and hormones (e.g., gastrin, VIP, 5-HT)
- Reduces intestinal and pancreatic secretions
- Slows gastrointestinal motility and inhibits gallbladder contraction
somatostatin like peptides adverse effects
- impaired pancreatic secretion cause STEATORRHEA -> fat soluble vitamin deficiency
- nausea, abdo pain
- GALLSTONES (50% of pts)
- prolonged treatment cause HYPOTHYROIDISM
- bradycardia
