Tx for Abd pain, Diarrhea, Constipation Flashcards
What are indications & SE of Linaclotide
IBS-Constipation pre dom subtype & chronic idiopathic constipation
SE: GI-related
what are indications and SEs of lubiprostone
IBS-C (women), chronic idiopathic constipation, opioid-induced constipation
SE: GI &/or CNS related
what is the efficacy of osmotic agents
large dose = 1-3 hrs
small dose= 0.5-3 days
What are the indications & SE for methylnaltrexone & naloxegol
opiod-induced constipation
SE - GI-related
what is loperamide
Chemically-_related_ to opiods
BUT does NOT exhibit analgesic/opiate-like effects/produce physical dependence
FDA issued drug safety communication –> cardiac toxicities leading to death
what can be used for pre-colonoscopy bowel prep
Na+ Picosulfate
Polyethylene glycol in large doses
What are stool softners
aka surfactant/emollient
docusate salts: Na+, Ca2+, K+
mineral oil
what are the indications, SE and warnings for alvimopan
ONLY for accelerating time to GI recovery after bowel resection SRG w/ primary anastomsis (prevention of post-op ileus_)_
SE: GI-related
Warning: risk of MI w/ use - REMS program; hospital only; max of 15 doses
what are MOA, indications and SE for antimuscarinics for GI
MOA: competitively (-) automonic, post-ganglionic cholinergic receptors
indications- Abd pain/spasm
SE: classic anticholinergic based (mad, blind, red, hot, dry)
what is Lactulose used for
severe liver dz (hyperammonemia) - change in pH traps ammonia in GI
adverse effect: electolyte disturbances ; GI related
What is diphenoxylate
synthetic opiate agonist (similar to meperidine)
class V
small quantity of atropine added to discourage deliberate abuse/OD
opiod effects at very high doses
what is the MOA for peripheral opiod antagonists
peripheral mu-opiod receptor antagonists
methylnaltrexone, naloxegol, alvimopan
what is the only indication of eluxadoline
IBS-D
What is the MOA of Linaclotide
selective guanylate cyclase-C agonist
bind on luminal surface of intestinal epithelium –> increase intracel/extracel concentration of cGMP –> (+) Cl-/HCO3- into intestinal lumen via CFTR
What are the classifications of Laxative & Cathartic agents
stimulants: bisacodyl, castor oil, glycerin, senna, Na+ picosulfate
osmotics: lactulose, Mg2+ citrate, PEF, sorbitol
saline: Mg2+ hydroxide, Na+ phosphate
bulk forming: dietary (fiber, bran, fruit, grain, cereal), psyllium, methylcellulose, carboxymethylcellulose, Ca2+ polycarbophil
stool softner: docusate, mineral oil
What is the MOA of Alosetron
selectively block GI-based 5-HT3 receptor –> modulate regulation of visceral pain, colonic transit & GI secretion
what are indications and SE of Crofelemer
Non-infxs diarrhea in HIV/AID (pt on ART)
SE: GI related (abd distension, elevated AST/ALT/bilirubin
infxn: resp/urinary
what classes of drugs can be used for Diarrhea
PG inhibitor: bismuth
Opioid agonists: loperamide, diphenoxylate, eluxadoline
5HT3 antagonists: alosteron
Cl- channel inhibitor: crofelemer
what are the adverse effects and drug interactions of bulk-forming/hydrophilic colloidal agents
bloating/obstruction (drink fluids - so caution in renal failure)
interactions= LOTS
what is the MOA and side effect of loperamide
MOA; interfere w/ peristalsis (slows transmit time); direct axn on circular/longitudinal Ms of intestinal wall –> slow motility –> allow fluid/electrolyte reabs & increase bulk/density of feces
SE: anticholinergic effects: “mad, blind, red, hot, dry”
What are the antimuscarinic agents that are used for abd pain
hyoscyamine
dicyclomine
How do anionic surfactants work
soften/lubricate feces
increase fluid secretion into GI tract
decrease fluid reabs from GI tract (mineral oils penetrate stool to soften)
What is PEG-3350
polytheylene glycol
large dose = bowel prep prior to GI scope, radiological procedures or SRG
small dose = constipation
what are saline agents
Mg2+ salts: Mg2+ sulfate & Mg2+ hydroxide
Na+ phosphate
poorly abs-ed –> hyperosmolar sol’ns & osmotically retain water in GI tract
greater vol shortens transit time
What are the classes of drugs used for constipation
laxative & cathartic agents
peripheral opiod antagonists- methylnaltrexone, naloxegol, alvimopan
guanylate cyclase-c agonist; linaclotide
selective Cl- (C2) channel activators: lubiprostone
what are osmotic agents
how does it work and what is the efficacy
lactulose
Mg2+ citrate
sorbitol
Polyethylene glycol (PEG)
=osmotically attract & retain increased water in colon–> increasing moisture, softness & vol/bulk
effect = 1-2+ days w/ laxative dose & large dose = catharsis
What are the safety protocols for prescribing alosetron
physician must enroll in prescribing program
pt & physicians must sign a risk-benefit statement & agree to adhere to therapy plans
additional self-training & testing by physicians to learn to appropriately Dx IBS required
no refills w/o a follow-up exam
what is the efficacy of stool softners
what are adverse effects
efficacy = 1-3+ days minimal laxative effect; softening mainly
adverse effects = GI-Related
what is the efficacy of stimulants?
what are adverse effects & contraindications
efficacy = 12-36 hrs
adverse effects: abd cramps; _Senna-_urine discolor (yellow-brown/red-pink); fluid/electrolyte distrubance
contraindication: GI obstruction/ileus/impaction
how do stimulants work
irritant to enterocytes, GI Sm. M leading to inflam –> Na/K ATPase inhibition &/or increase in PG synthesis/secretion (via cAMP/cGMP)
promote water/electrolyte accumulation in GI - castor oil is hydrolyzed to ricinoleic acid
stimulate peristalsis
How do bulk-forming/hydrophilic colloidal agents work
what is the efficacy
work to increase bulk-volume & water content –> increase GI motility
fiber can support colonic bacteria, fermentation & digestion
efficacy in 2-4+ days
what are drug interactions & cautions of saline agents
interaction = diuretics (electrolyte balance)
cautions: renal dz (electrolyte) & CHF/HTN (Na+)
What are indications for Alosetron
chronic, severe IBS-D not responsive to other conventional therapies (women)
severe IBS-D = diarrhea, freq/severe abd pain, freq bowel urgency/fecal incontinence, restriction of daily activity due to IBS
(exclude anatomic/biochem GI abnormalities before prescribing)
what do you use as a stimulant for infants who cant defecate
glycerin
tri-hydroxyl alcohol - fxn as irritant, osmotic, lubricant agents
What are examples of stimulants
senna
bisacodyl
castor oil
glycerin
Na+ picosulfate
What are SE and contraindications of alosetron
GI related
black box: ischemic colitis
-> containdication =
- GI obstruction, perforation, stricture/adhesion, toxic megacolon
- diverticulitis, crohns, UC
- impaired instestinal circulation, thrombophlebitis or hypercoag state
- severe constipation: D/C immediately if develops on alosetron therapy
What is the MOA of eluxadoline
agonist at opioid mu & kappa receptor in GI (slow peristalsis/delays digestion)
AND antagonist at delta receptor in GI (stomach, pancreas, biliary secretions decreased)
What are contraindications for eluxadoline
biliary duct obstruction
alcoholism
Hx of pancreatitis
severe hepatic impairment
ALSO - stop if severe constipation develops & lasts 4+days & conitnue after bowels return to normal
what is the MOA and SE of diphenoxylate
MOA: exert effect locally & centrally on GI Sm M cells –> inhibit GI motility –> slow excess GI propulsion
SE: anticholinergic; atropine “mad, blind, hot, red, dry”
what are the SEs of Eluxadoline
hepatic/pancreatic toxicity (increased enzymes) ==> pancreatitis high risk pts w/o a gallbladder; FDA warning - death
CNS-related - sedation/euphoria/impaired cognition
What is the MOA of Lubiprostone
a PGE-1 derivative –> increase intestinal fluid secretion by activating GI specific Cl- channel (CIC-2) in luminal cells of interstional epithelium
What is Crofelemer & what is its MOA
derived from dark red sap of Croton lechleri tree (botanical pharm)
(-) Cl- secretion by blocking cAMP stimulated CFTR & Ca-activated Cl-channel
channels regulate fluid secretion by intestinal epithelial cells
