Constipation & Diarrhea Flashcards
(12 cards)
What non-drug treatment is preferred to treat constipation?
- Increasing fluid intake
- Limiting caffeine and alcohol (to avoid dehydration)
- Increasing physical activity
- Replacing refined foods with whole grain products & food high in fiber
What are 6 drug classes that may cause constipation?
- antidiarrheals
- anticholinergics
- cation-containing drugs (aluminum, calcium)
- colesevelam
- opioids
- antihypertensives (clonidine, non-DHP CCBs)
What is the MOA of bulk forming, osmotic, stimulant, stool softeners, and lubricant laxatives?
Bulk forming: absorb water in the intestine, which adds bulk to the stool. This increases peristalsis and decreases stool transit time.
- soluble fiber, psyllium
- preferred in pregnancy
Osmotics: draw fluid into the bowel lumen through osmosis
- PEG
Stimulants: directly stimulate neurons in the colon.
- senna, bisacodyl
Stool softeners: emollients that reduce the surface tension of the stool, allowing more water to mix with the stool
- docusate
Lubricants: coats the bowel and stool with a waterproof film
- mineral oil
What drug class are these medications in: psyllium, calcium polycarbophil, methylcellulose, wheat dextrin? What are their brand names? What is a note about fluid intake? What is important about calcium polycarbophil administration?
Bulk-forming drugs
- psyllium (Metamucil)
- calcium polycarbophil (FiberCon)
- methylcellulose (Citrucel)
- wheat dextrin (Benefiber)
Adequate fluids are required (these absorb water into the intestine, which adds bulk to the stool)
Separate calcium polycarbophil from select drugs due to the binding interactions
What drug class are these medications in: magnesium hydroxide, polyethylene glycol, glycerin, lactulose, sodium phosphates? What is one unique side effect? What medication should be used with caution in renal impairment?
Osmotics
Side effect: electrolyte imbalance
Caution using magnesium-containing products in renal impairment. Do not using if severe renal impairment
What drug class are these medications in: senna, senna/docusate, bisacodyl? When should these oral products be taken and why?
Stimulant laxatives
The onset of action is 6-12 hours, so it could be taken at bedtime to induce a bowel movement the following morning
What drug class is docusate in? When would it the preferred treatment?
Emollient (stool softener)
Preferred when straining should be avoided (postpartum, post-MI, anal fissures, hemorrhoids), and when stool is hard or dry.
What indications do lubiprostone, linaclotide/plecanatide, alvimopan, methylnaltrexone/naloxegol/maldemedine, and prucalopride have? What are their MOAs?
Options: chronic idiopathic constipation, IBS-C, opioid induced constipation, and surgery
lubiprostone: CIC, IBS-C (in adult women), OIC
- chloride channel activator, leading to increased fluid secretion and peristalsis
linaclotide, plecanatide: CIC, IBS-C
- gluanylate cyclase C agonist, increasing speed of GI transit and reducing abdominal pain
alvimopan: surgery (used to decrease risk of post-op ileus)
- peripherally-acting mu-opioid receptor antagonist, decreases constipation
- max of 15 doses
- cannot use if therapeutic doses of opioids for > 7 consecutive days prior to use
methylnaltrexone, naloxegol, naldemedine: OIC
prucalopride: CIC
- serotonin 5-HR4 receptor agonist, causes muscle contractions and increases GI motility
- warning for suicidal ideation
What is the brand names for bowel irrigation for these drugs: polyethylene glycol-electrolyte solution, sodium phosphates, sodium sulfate/potassium sulfate/magnesium sulfate? Which whole bowel irrigation has a boxed warning for nephropathy?
- PEG-electrolyte solution (Colyte, GoLytely)
- sodium phosphates (OsmoPrep)
- sodium sulfate, potassium sulfate, magnesium sulfate (Suprep Bowel Prep Kit)
OsmoPrep has a boxed warning for nephropathy
What is eluxadoline’s MOA and when is it indicated?
Eluxadoline (Vibrezi) - mixed mu-opioid receptor agonist, so it binds to the opioid receptors as an agonist to treat diarrhea
Indicated for IBS-D
What is the brand name of bismuth subsalicylate? What are 5 contraindications, 1 warning, and 3 side effects?
bismuth subsalicylte (Pepto-Bismol)
Contraindications
- salicylate allergy
- taking other salicylates
- GI ulcer
- bleeding problems
- black/bloody stool
Warning
- children and teenagers who are recovering from the flu, chickenpox, or other viral infections should NOT use this due to Reye’s syndrome
Side effects
- black tongue/stool
- salicylate toxicity (tinnitus)
- nausea
