Diarrhea and Constipation Info

Question 1

Cisapride

Answer 1

5HT4 receptor agonist. Leads to increase motility (prokinetic). used as a last resort, used for diabetic gastroporesis
AE: long Qt syndrome, cardiovascular toxicity

Question 2

Domperidone

Answer 2

Dopamine D2 antagonist, increases actions of ACH in gut, produces inhibition of dopamine inhibition leading to increased motility and gut. Used for compassionate use only in the US in cases of impaired motility like vagotomy, diabetic gastroporesis.
AE: somnolence, nervousness, agitation, anxiety, dystonia, parkinson related sx. also leads to increased prolactin release and can cause impotence, menstral disorders and galactorrhea.

Question 3

Erythromycin

Answer 3

Macrolide Antibiotic (23S) acts as a motilin receptor agonist inducing the migrating motor complex.

Question 4

Metoclopramide

Answer 4

Dopamine D2 antagonist, increases actions of ACH in gut, produces inhibition of dopamine inhibition leading to increased motility and gut. for cases of impaired motility like vagotomy, diabetic gastroporesis.
AE: somnolence, nervousness, agitation, anxiety, dystonia, parkinson related sx. also leads to increased prolactin release and can cause impotence, menstral disorders and galactorrhea.

Question 5

Diphenoxylate

Answer 5

Enkaphalin decreases both GI motility and water excretion. available by prescription with atropine due to some euphoric effects. most effective antidiarrheals
AE: abdominal cramps, toxic megacolon if pt has ulcerative colitis, euphoria.

Question 6

Loperamide

Answer 6

Enkaphalin decreases both GI motility and water excretion. available OTC no crossing of BBB most effective antidiarrheals
AE: abdominal cramps, toxic megacolon if pt has ulcerative colitis,

Question 7

Cholestyramine

Answer 7

Bile acid binding resin, decreases bile acid anion exchange preventing secratory diarrhea.
AE: frequent GI effects, bloating flattulence, constipation and fecal impaction. see impaired absorbtion of other drugs and fat soluble vitamins.

Question 8

Colestipol

Answer 8

Bile acid binding resin, decreases bile acid anion exchange preventing secratory diarrhea.
AE: frequent GI effects, bloating flattulence, constipation and fecal impaction. see impaired absorbtion of other drugs and fat soluble vitamins.

Question 9

Kaolin

Answer 9

Combination with Pectin acts as a bulk fiber increasing fluid, causing distention in the bowel and increased motility

Question 10

Bismuth Subsalicylate

Answer 10

salycilate decreases prostaglandins and Cl secretion in large intestine, also is an antimicrobial binding enterotoins in gut. Prevents and treats traveler’s diarrhea.
AE: blackening of stool and tongue, high doses lead to salycilate toxicity, tinnitus and acid base abnormalities

Question 11

Crofelemer

Answer 11

Voltage independant inhibitor of CFTR and another Cl- channel leading to decreased CL secretion and another Cl channel leading to decreased na and H2O in stool, more formed stool. Little systemic absorption,
Used for anti HIV drug treatment.

Question 12

Octreotide

Answer 12

Somatostatin analog, in low doses decreases fluid secretion, increases motility, high doses decreases motility.
Off label Used to treat severe diarrhea due to HIV treatmint, dumping syndrome, and short bowel syndrome
AE: decreased pancreatic secretion, decreased motility, nausea, decreased gallbladder contractility, insulin glucagon imbalance, hypothyroidism

Question 13

Docusate

Answer 13

stool softener: surfactant, mixes fats and water, lubricates stool, mildest of laxatives

Question 14

Mineral Oil

Answer 14

Stool softener: lubricates stool used OTC, mildest of laxatives, can result in severe lipid pneumonitis if aspirated and long term use can lead to decreased absorption of fat sol vitamins: ADEK

Question 15

Methylcellulose

Answer 15

Bulk Laxative which Attracts water and increases mass in the stool leading to lumen distension and increased seritonin release from the Enterchromaffin cells causing increased peristalsis

Question 16

Psyllium

Answer 16

Bulk Laxative which Attracts water and increases mass in the stool leading to lumen distension and increased seritonin release from the Enterchromaffin cells causing increased peristalsis

Question 17

Linaclotide

Answer 17

Activates guanylyl cyclase C leading to increased cGMP activating CFTR, Cl secretion and increased water in lumen. Little systemic absorption.
AE; diarrhea, maternal death, not used on kids.

Question 18

Lubiprostone

Answer 18

Increases CCK 2 leading to increased CL secretion and increased fluid in the gut. treats chronic constipation and has poor absorption so limited systemic side effects.
AE: nausea, headache, diarrhea, FETAL LOSS

Question 19

Alvimopan

Answer 19

Opioid mu receptor antagonist, only works in the enteric, cannot cross BBB Treats constipation caused by opioid therapy. Used only for short term hospital patients due to increased risk of MI.

Question 20

Methyl naltrexone

Answer 20

Opioid mu receptor antagonist, only works in the enteric, cannot cross BBB Treats constipation caused by opioid therapy, used for chronic and long term palliative care.

Question 21

Lactulose

Answer 21

Osmotic Cathartic not absorbed, increases water in lumen by osmosis. leads to increased stretch sensation and used for constipation when the enteric nervous system has been disrupted. Decreases plasma ammonia concentration
AE: portal systemic encephalopathy, electrolyte imbalances, arrhytmias, digested by gut bacteria- flatulence, cramps

Question 22

Magnesium Hydroxide

Answer 22

Osmotic Cathartic not absorbed, increases water in lumen by osmosis. leads to increased stretch sensation and used for constipation when the enteric nervous system has been disrupted.
AE: portal systemic encephalopathy electrolyte imbalances, arrhytmias, hypermagnesium in kidney failure patients

Question 23

Sodium Phosphate

Answer 23

Osmotic Cathartic not absorbed, increases water in lumen by osmosis. leads to increased stretch sensation and used for constipation when the enteric nervous system has been disrupted.
AE: portal systemic encephalopathy electrolyte imbalances, arrhytmias

Question 24

Polyethylene Glycol solution

Answer 24

Osmotic Cathartic not absorbed, increases water in lumen by osmosis. leads to increased stretch sensation and used for constipation when the enteric nervous system has been disrupted.
AE: portal systemic encephalopathy electrolyte imbalances, arrhytmias

Question 25

Alosetron

Answer 25

5HT3 Serotonin receptor Antagonist preventing the transmission through the affarent fibers, decreased sensation, decreased peristalsis. Used for diarrhea prominent IBS, restricted availability Compassionate use
AE: constipation requiring hospitalization, ischemic colitis CYP1A2,

Question 26

Tegaserod

Answer 26

5HT4 Agonist Leads to increase motility (prokinetic). used as a last resort, used for constipation predominant IBS
AE: cardiovascular toxicity, arrhythmia

Question 27

Amitriptyline

Answer 27

Ticyclic antidepressant decreases reuptake of NE from postganglionic sympathetic neurons activates alpha 2 on presynaptic terminals of the postganglionic parasympathetic nerves, decreased ACH release and motility. decreases reuptake of dopamine and increases activation of D2 receptors, decrease ACH decreased motility

Question 28

Desipramine

Answer 28

Ticyclic antidepressant decreases reuptake of NE from postganglionic sympathetic neurons activates alpha 2 on presynaptic terminals of the postganglionic parasympathetic nerves, decreased ACH release and motility. decreases reuptake of dopamine and increases activation of D2 receptors, decrease ACH decreased motility

Question 29

Paroxetine

Answer 29

SSRI Increases Seritonin in the synapse of the sensory neuron to the myenteric plexus leading to increased inhibition of enkephalons, and increased peristalsis

Question 30

Fluoxitine

Answer 30

SSRI Increases Seritonin in the synapse of the sensory neuron to the myenteric plexus leading to increased inhibition of enkephalons, and increased peristalsis

Question 31

Sertaline

Answer 31

SSRI Increases Seritonin in the synapse of the sensory neuron to the myenteric plexus leading to increased inhibition of enkephalons, and increased peristalsis

Question 32

Polycarbophil

Answer 32

Bulk Laxative which Attracts water and increases mass in the stool leading to lumen distension and increased seritonin release from the Enterchromaffin cells causing increased peristalsis

Question 33

Anthraquinone

Answer 33

Contact cathartic acts on the large intestine, leads to irritation of the bowel and increased peristalsis through the enteric nervous system.
AE: dependancy and destroys the myenteric plexus with long term use.

Question 34

Bisacodyl

Answer 34

Contact cathartic acts on the large intestine, leads to irritation of the bowel and increased peristalsis through the enteric nervous system.
AE: dependancy and destroys the myenteric plexus with long term use.

Question 35

Castor Oil

Answer 35

Contact cathartic acts on the large and small intestines, leads to irritation of the bowel and increased peristalsis through the enteric nervous system. Very rapid and potent effects.
AE: Causes dehydration and electrolyte imbalances, UTERINE Contractions. dependancy and destroys the myenteric plexus with long term use.

Question 36

Cascara Sagrada

Answer 36

Anthraquinone: Contact cathartic acts on the large intestine, leads to irritation of the bowel and increased peristalsis through the enteric nervous system.
AE: dependancy and destroys the myenteric plexus with long term use.

Question 37

Danthron

Answer 37

Anthraquinone: Contact cathartic acts on the large intestine, leads to irritation of the bowel and increased peristalsis through the enteric nervous system.
AE: dependancy and destroys the myenteric plexus with long term use.

Question 38

Senna

Answer 38

Anthraquinone: Contact cathartic acts on the large intestine, leads to irritation of the bowel and increased peristalsis through the enteric nervous system.
AE: dependancy and destroys the myenteric plexus with long term use.