GI- diarrhea and constipation crap

Question 1

Metoclopramide

Answer 1

1. D2 receptor antagonist- enhances motility and tone of SM in the upper GI tract and esophageal sphincter
2. uses:
   - antiemetic- acts on CTZ in CNS
   - dec. gastric hypomotility and associated nausea and vomiting
3. SE:
   - cramping and diarrhea
   - at high doses: extrapyramidal sx, and exacterbation of parkinsons disease, depression, anxiety
4. CI:
   - pregnancy

Question 2

Bethanechol

Answer 2

1. muscarinic agonist that inc GI motility and tone
2. uses
   - tx postop ileus
   - inc lower esophageal sphincter tone
   - DOES NOT get into CNS - no CNS SE
3. SE
   - muscarinic issues: cramping, diarrhea, salivation, sweating, etc.
   -

Question 3

Anti-spasmotics, or Anti-cholinergic agents in GI

Answer 3

• Glycopyrrolate, and dicyclomine
• used as GI anti-spasmotics , dec intestinal overactivity and reduce cramping and spasms,
  SE: sedation, dry mouth, constipation

Question 4

Alosetron

Answer 4

1. Blocks 5-HT3 receptors (regulate visceral pain, colonic transit, and GI secretion)
2. USES:
   - tx women w/severe diarrhea predominant IBS that has failed with other treatments (pt and dr have to sign risk-benefit agreement)
3. SE:
   - constipation
   - GI obstruction, GI perforation, impaction, toxic megacolon, secondary ischemic colitis, death
4. CI
   - ischemia or uc, constipation,
   - anything seriously wrong with the GI- don’t take, also with vascular issues of the GI

Question 5

TCA

Answer 5

• tx IBS because of the anti-cholinergic effects to dec. spasticity and improve chronic pain

Question 6

Ondansetron (“–setron)

Answer 6

1. anti-emetic- selectively blocks 5HT3 receptors in teh CTZ and in the GI tract
2. uses
   - tx vomitinn in chemotherapy, and with vagal stimulation pathologies (GI distenstion, gastroenteritis)
   - NOT effective for vomiting due to motion sickness- not sedating

Question 7

Procholorperazine, and promethazine

Answer 7

1. Phenothiazines, and Buytrophenones- block Dopamine, muscarinic, and histamine receptors - anti-emetic
   TX: post op nausea and vomiting, cause significant sedation

Question 8

Cannabinoids

Answer 8

1. Dronabinol, Nabilone
2. anti-emetic, mech unknown
3. combined w/procholorperazine or promethazine to inc effectiveness off both

Question 9

Bisacodyl

Answer 9

1. laxative

2. act on the bowel to inhibit absorption of water and may sitmulate peristalsis

Question 10

Castor oil

Answer 10

1. laxative
2. requires presence of bile- dont use when biliary obstruction
   - used to prepare bowel for diagnostic procedures
   CI: pregnacy- can stimulate the uterus

Question 11

mineral oil

Answer 11

stool softener

• it can dec. absorption of fat soluble vitamins
• if inhaled: lipoid pneumonia

Question 12

Ducosate Sodium

Answer 12

stool softener

- emulsifying agent that allows water to penetrate the colonic contents and soften them

Question 13

Glycerin

Answer 13

Stool softener

- suppository, lubricates the distal end of the bowel- irritation from glycerin can stimulate peristalsis

Question 14

Lubiprostone

Answer 14

1. laxative, Prostaglandin E1 derivative- inc. intestinal fluid secretion by activation chloride channels in the luminal cells of the intestingal epithelium
2. uses
   - soften stools and inc. intestinal motility, promoting spontaneous bowel movements
   - reduces sx chronic constipation
3. does not alter electrolytes, does not produce tolerance, well tolerated

Question 15

Alvimopan, methylnaltrexone

Answer 15

1. Laxative - mu antagonist that acts selectively on the GI tract
2. Uses
   - antagonize opioid induced inhibition of the gastric motility and ileus when opioids are used to tx pain
3. SE:
   - constipation, flatulence
   - anemia, dyspepsia, hypokalemia, back pain, and urinary retention
4. ci
   - severe hepatic impairment, end stage renal disease, or in pts undergoing surgery for correction of complete bowel obstruction

Question 16

Loperamine

Answer 16

1. Anti-diarrhetic, opioid derivative- dec. peristalsis
   - no CNS effects and has low abuse potential
   SE:
   - ab pain, distention, constipation, dry mouth, hypersensitivity, nausea, vomiting
   CI:
   - in diarrhea caused by organisms that penetrate the intestinal muscosa
   - in pts with UC
   - in pts addicted to opioids or with a hx of abuse

Question 17

Lotmotil (diphenoxylate plus atropine)

Answer 17

• anti diarrhea
• opioid and atropine (inhibits cholinergic)
• has CNS effects and thus abuse potential, dec by combination with atropine

Question 18

Simethicone (Gas X)

Answer 18

antiflatulent that coats and dissipates gas to make it pass with less of a noticable effect

Question 19

Sulfasalazine

Answer 19

IBD (Crohns and UC) drug-
dec inflammation
SE:
- HA, nausea, fatigue, and rash

Question 20

TNF agents

Answer 20

• approved for use for UC

- “MAB”