IBS drugs

Question 1

rifaximin moa

Answer 1

inhibits bacterial RNA synthesis (antibiotic), alters GI flora to regain balanced microbiome

Question 2

rifaximin indication

Answer 2

IBS-D

Question 3

rifaximin AE

Answer 3

well tolerated due to minimal systemic absorption: dizziness, nausea, headache

Question 4

antispasmodics moa

Answer 4

relax smooth muscle and attenuation of visceral hypersensitivity and pain sensation

Question 5

antispasmodics indications

Answer 5

IBS-associated abdominal pain (will not help with constipation or diarrhea, just pain)

Question 6

antispasmodics duration of therapy

Answer 6

short term relief: anticholinergic adverse effects limit long term use

Question 7

anticholinergic adverse effects of antispasmodics

Answer 7

drowsiness, heat intolerance, tachycardia, xerostomia, urinary retention, constipation, blurred vision

Question 8

what is first line treatment for IBS-C and IBS-D

Answer 8

TCAs

Question 9

TCA dosing pearls

Answer 9

efficacious for IBS at lower doses than those used for depression, start out at a low dose and titrate to a therapeutic dose while minimizing AEs

Question 10

TCA mechanism

Answer 10

inhibits norepinephrine and dopamine reuptake to improve visceral pain, anticholinergic effects improve visceral pain and slow GI transit, increasing serotonin/norepinephrine/ dopamine improves psychological distress

Question 11

_____ generally have less anticholinergic effects

Answer 11

secondary amines (nortriptyline, desipramine)

Question 12

alosetron MOA

Answer 12

5HT-3 receptors are ligand-gated ion channels that line the GI tract; blocking them reduces abdominal discomfort, slows colonic transit, and reduces diarrhea

Question 13

alosetron indications

Answer 13

women with severe IBS-D that is unresponsive to conventional therapy

Question 14

alosetron AE

Answer 14

constipation (hold therapy until resolution and restart at a lower dose), ischemic colitis (discontinue therapy and DO NOT restart–> REMS)

Question 15

eluxadoline moa

Answer 15

mu and kappa opioid receptor agonism controls GI motility and decreases diarrhea

Question 16

eluxadoline narcotic effects?

Answer 16

binds to opioid receptors in the GI tract, making it peripherally acting and no narcotic effects

Question 17

eluxadoline indication

Answer 17

IBS-D

Question 18

eluxadoline pearl

Answer 18

reduce dose in mild or moderate hepatic dysfunction

Question 19

eluxadoline contraindications

Answer 19

gullbladder removal, severe hepatic dysfunction, pancreatitis, alcohol abuse

Question 20

linaclotide and plecanatide mechanism

Answer 20

guanylate cyclase c agonist: increases secretion of chloride and bicarb into intestinal lumen. pro-secretory agent: Cl pulls H2O into the intestinal tract and increases peristalsis

Question 21

linaclotide and plecanatide AE

Answer 21

diarrhea

Question 22

linaclotide and plecanatide indication

Answer 22

IBS-C

Question 23

plecanatide pearl

Answer 23

dispensed in a blister pack to improve compliance

Question 24

linaclotide pearl

Answer 24

gi bleeding but rare

Question 25

lubiprostone MOA

Answer 25

prostaglandin E1 analog/chloride channel activator: promotes fluid secretion into the GI tract and increases peristalsis, pro-secretory agent

Question 26

lubiprostone indication

Answer 26

IBS-C

Question 27

lubiprostone AE

Answer 27

diarrhea, nausea, may be a delay in initial response