GI Pt 2 Flashcards
What are the 2 mechanisms that Metoclopramide (Reglan) contribute to prokinetic activity?
- serotonin receptor agonist
- dopamine receptor blocker
both increase motility by stimulating Ach production
Which of the prokinetic agents will stimulate cholinergic receptors in the entire body, leading to side effects such as dry eyes.
a. bethanechol
b. metoclopramide
c. domperidone
d. erythromycin
a. bethanechol
A patient prescribed metoclopramide is most at risk for which of the following?
a. achlorhydria
b. constipation
c. extrapyramidal symptoms
c. xerostomia
c. extrapyramidal symptoms
What are the 2 indications for metoclopramide?
- promote peristalsis
- suppress sensation of nausea/vomiting
What extrapyramidal symptom is the most concerning with metoclopramide?
- tardive dyskinesia
A 71 yo patient who consumes a scoop of psyllium mixed with OJ every morning is most at risk for which of the following?
a. drug interactions of absorption
b. impaired kidney function
c. hepatotoxicity
d. vitamin C intoxication
e. all of the above
a. drug interactions of absorption
How do osmotic agents enhance peristalsis?
- osmotically mediated water retention
For saline-based osmotic agents you need to closely monitor electrolytes in which patient populations?
- renal or CV disease
- underlying electrolyte disorders or on diuretics
Anything that contains this mineral is by definition under the saline-based osmotic agents
- magnesium
What is the trouble with administering glycerin orally?
- it does not reach the intestinal tract
* need to be given rectally
Polyethylene glycol (PEG 3350) are commonly used before what procedure?
- colonoscopy
Which type of osmotic agents has no absorption so you do not need to worry about anything systemic?
- sugar/alcohol-based
e. g. Lactulose
Why do you not want a patient to be on stimulant laxatives permanently?
(e.g. Bisacodyl)
- Could create a dependence
What are the 2 effects of stimulating cGMP in the epithelial cell?
- stimulate CFTR which secretes Cl/HCO3 into lumen
- decreases afferent pain fibers
For IBD which is primarily constipation in general you want a drug that can stimulate the what receptor?
- GC-C receptor
Which of the following drugs is a type 2 chloride channel agonist?
a. lubiprostone
b. linaclotide
c. plecanatide
a. lubiprostone
Which of the following drugs is a guanylate cyclase (GC-C) agonists?
a. lubiprostone
b. linaclotide
c. plecanatide
d. both b and d
d. both b and d
What are the 3 drug classes that are used for CIC or IBS-C?
- serotonin receptor agonists
- GC-C agonists
- Type 2 chloride channel agonist
Which of the following drugs is a stool softener?
a. docusate
b. psyllium
c. Mg or Phos salts
d. Bisacodyl
e. Lubriprostone
a. docusate
Which of the following drugs is a bulk forming agent?
a. docusate
b. psyllium
c. Mg or Phos salts
d. Bisacodyl
e. Lubriprostone
b. psyllium
Which of the following drugs is an osmotic agent?
a. docusate
b. psyllium
c. Mg or Phos salts
d. Bisacodyl
e. Lubriprostone
c. Mg or Phos salts
Which of the following is a PEG solution?
a. docusate
b. psyllium
c. Miralax
d. Bisacodyl
e. Lubriprostone
c. Miralax
Which of the following is a stimulant?
a. docusate
b. psyllium
c. Miralax
d. Bisacodyl
e. Lubriprostone
d. Bisacodyl
A patient with opioid induced constipation has attempted all first line therapies without any success. What drug class would you try next?
- Peripherally Acting Mu-Opioid Receptor Antagonists (PAMORA)
What bulk forming agents and/or binding agents work as anti-diarrheals? (2)
- psyllium
- bismuth
Loperamide is a derivative of what?
used as an anti-motility agent
- meperedine (demarol)
What is the benefit of using Loperamide as an anti-motility agent?
- it does not cross the blood brain barrier so it does not produce the same effects as opioids
Why is Diphenoxylate prescription only?
- at higher doses it can cross the blood brain barrier
Why is Diphenoxylate almost always combined with Atropine?
brand name: Lomotil
- to reduce the chances of overdosing in Diphenoxylate because Atropine at high doses has many side effects
What are the 3 anti-motility agents we ought to remember?
- opioids
- loperamide
- diphenoxylate