Treatments for Diarrhea, Abdominal Pain and Constipation Flashcards
What drug classes are indicated for diarrhea?
- prostaglandin inhibitors
- opioid agonists
- serotonin (5HT3) antagonists
- chloride channel inhibitors
What drugs are in the prostaglandin inhibitor class?
bismuth
What drugs are in the opioid agonist class?
- Loperamide
- Eluxadoline
- Diphenoxylate
What drugs are in the serotonin (5HT3) antagonist class?
- alosetron
What drugs are in the chloride channel inhibitor class?
- Crofelemer
What drug classes are indicated for abdominal pain?
- antimuscarinic agents
(hyoscamine, dicyclomine)
What drugs are in the anti-muscarinic class?
- hyoscyamine
- dicyclomine
What drug classes are indicated for constipation?
- peripheral opioid antagonists
- guanylate cyclase-C agonists
- selective chloride (C2) channel activators
- laxatives and cathartics
What drugs are in the peripheral opioid antagonist class?
- Methylnaltrexone
- Alvimopan
- Naloxegol
What drugs are in the guanylate cyclase-C agonist class?
- Linaclotide
What drugs are in the selective chloride (C2) channel activators?
- Lubriprostone
What drug classes are in the laxative and cathartic agents?
- stimulants
- osmotics
- salines
- bulk forming
- stool softeners
What drugs are classified as stimulants?
- Bisacodyl
- Castor oil
- Glycerin
- Senna
- Na+ Picosulfate
What drugs are classified as osmotics?
- Lactulose
- Magnesium Citrate
- Polyethylene glycol
- Sorbitol
- Glycerin
What drugs are classified as salines?
- Magnesium hydroxide
- Na+ phosphate
What drugs are classified as bulk-forming?
- Diet (fiber/bran)
- Psyllium
- methylcellulose
- carboxymethylcellulose
- calcium polycarbophil
What drugs are classified as stool softeners?
- docusate
- mineral oil
Loperamide
MOA, side effects
MOA:
- chemically related to opioids but no analgesic effects
- interferes w/peristalsis
Side effects:
- cardiac toxicities
- anticholinergic toxicities
Diphenoxylate
MOA, side effects
MOA:
- synthetic opiate agonist + some atropine to prevent abuse/overdose
- inhibit GI motility via local & central effect on GI smooth muscle
Side effects:
- anticholinergic toxicity + atropine toxicity
Eluxadoline
MOA, side effects
MOA:
- agonist of opioid mu & kappa; slow peristalsis
- antagonist of opioid delta; decrease GI secretions
Side effects:
- IBS, diarrhea-predominant (IBS-D)
- hepatic/pancreatic toxicities (higher if no gallbladder)
What is Eluxadoline contraindicated in?
- biliary duct obstruction
- alcoholism
- hx of pancreatitis
- severe hepatic impairment
When should you stop Eluxadoline?
if you get severe constipation and it lasts 4+ days
Alosetron
MOA, side effects
MOA:
- selectively block GI 5HT3 receptors
- inhibit GI secretions
Side effects:
- ischemic colitis (BLACK BOX)
What is Alosetron indicated for?
chronic/severe IBS-D that is unresponsive to other therapies
- only for women
Crofelemer
MOA, side effects
MOA:
- block cAMP-stimulated CFTR and CaCC to inhibit Cl- secretion
Side effects:
- abdominal distention
- elevated AST/ALT/bilirubin
What is Crofelemer indicated for?
non-infectious diarrhea in HIV/AIDS
pts on anti-retroviral therapy
Hyoscamine, Dicyclomine
MOA, side effects
MOA:
- competitive muscarinic antagonists
Side effects:
- anticholinergic toxicity
Methylnaltrexone, Naloxegol, Alvimopan
MOA
MOA:
- peripheral mu-opioid receptor antagonists
- stimulate GI progression
Which peripheral opioid antagonist is indicated for hospital-use only?
Alvimopan
prevention of post-op ileus, bowel resection surgery
Which peripheral opioid antagonists are indicated for opioid-induced constipation?
- methylnaltrexone
- naloxegol
What is the one warning for Alvimopan?
- risk of MI
- do not exceed 15 doses
Linaclotide
MOA, indication
MOA:
- guanylate cyclase-C agonist (increase cGMP)
- stimulate secretion of Cl & HCO3 into lumen via CFTR activation
Indication:
- IBS-C
- chronic idiopathic constipation (CIC)
Lubiprostone
MOA, indications
MOA:
- PGE-1 derivative, increase intestinal fluid secretion by activating GI-specific chloride channels (CIC-2)
Indications:
- IBS-C (non-pregnant women)
- CIC
- OIC
Bulk-forming/hydrophilic colloidal agents
MOA, efficacy
MOA:
- increase bulk volume and water content, increases GI motility
Efficacy:
- 2-4+ days
Stool softeners
MOA, efficacy
MOA:
- increase fluid secretion into GI tract
- decrease fluid reabsorption in GI tract
Efficacy:
- 1-3+ days
Stimulants ***
MOA, efficacy
MOA:
- irritate enterocytes
- Na/K ATPase inhibition
- increase prostaglandin secretion
Efficacy:
- 12-36 hours
Adverse effects of stimulants?
- abdominal cramping
- urine discoloration with use of Senna (yellow/brown to red/pink)
Saline agents
MOA
MOA:
- hyperosmolar, keeps water in GI tract
What should you be cautious about when using saline agents?
- renal disease
- CHF/HTN (sodium)
Osmotic agents
MOA, efficacy
MOA:
- attract/retain water in GI tract
Efficacy:
- 1-2+ days (1-3 hrs if large dose)
What is a special use of lactulose?
severe liver disease
- causes hyperammonemia in GI tract
What is the special use of polyethylene glycol?
bowel prep for GI scopes/surgery
large doses
