GI Agents Spark Notes

Question 1

Histamine-2 Antagonists: mechanism of action

Answer 1

• Selectively blocks H2 receptors
• Prevents about 70% of hydrochloric acid release
• Decreases pepsin productions

Question 2

PPI Medication interactions

Answer 2

• Benzodiazepines
• Phenytoin
• Warfarin
• Ketoconazole
• Theophylline
• Some antiretroviral meds (Contraindicated with HIV treatment meds)

Question 3

Misoprostol Indications

Answer 3

• NOT FOR PREGNANCY
• Prevention of NSAID-induced gastric ulcers in patients at high risk of complications

Question 4

Antacid use and health concerns

Answer 4

• Overuse can cause kidney stones
• Can cause alkalosis (confusion, tremors, numbness, N/V)
• Can cause hypercalcemia (thirst, frequent urination, confusion, fatigue)
• Can cause hypophosphatemia (muscle pain, weakness, numbness, altered mental status)

Question 5

Psyllium teachings

Answer 5

• Bulks up the stool in cases of diverticulosis or IBS
• Separate from all other meds by 2 hours or it can mess with absorption
• Take with at least 8oz of water

Question 6

Lactulose indications

Answer 6

• Used for high ammonia levels (should be less than 3 micromol/L)
• Osmotic laxative for acute conditions

Question 7

Metoclopramide AE

Answer 7

• BOXED WARNING FOR TARDIVE DYSKINESIA (lip smacking, tongue protrusion, rapid jerking movements (chorea), slow writhing movements (athetosis), tapping feet, repetitive chewing, restlessness)
• N/V, diarrhea, intestinal spasms, cramping
• Declining blood pressure and heart rate, weakness, fatigue, seizure

Question 8

Lubiprostone TA

Answer 8

• locally acting chloride channel activators; for IBS with constipation

Question 9

Ondansetron AE

Answer 9

• CNS (headache, dizziness, myalgia)
• Pain at injection site, rash, constipation, diarrhea, hypotension, urinary retention

Question 10

Ondansetron TA

Answer 10

• Blocks receptors associated with N/V in the CTZ and locally

Question 11

Promethazine AE

Answer 11

• Autonomic effects (drowsiness, dizziness, weakness, tremors, tachycardia, hypotension, cardiac arrhythmias, urinary hesitancy/retention, dry mouth, constipation)
• Extrapyramidal symptoms (restlessness, tremors, tongue protrusion, muscle contractions)

Question 12

Promethazine and Autonomic side effects

Answer 12

• Drowsiness, dizziness, weakness, tremors, hypotension, cardiac arrhythmias, urinary hesitancy/retention, dry mouth, constipation

Question 13

Agent for treating vestibular problems

Answer 13

Meclizine

Question 14

5-HT3 receptor blocker and SSRI/SNRI interactions

Answer 14

• Serotonergic medications: citalopram (SSRI) and duloxetine (SNRI) (can cause serotonin syndrome)
• SEVERE SEROTONIN SYNDROME (high fever, tremors, seizures, irregular heartbeat, unconsciousness)

Question 15

Agents to treat nausea: various routes

Answer 15

Promethazine: Injection or IV

Ondansetron: Injection, oral, IV

Question 16

Sucralfate: medication interactions

Answer 16

• Aluminum salts
• Phenytoin
• Digoxin
• Warfarin
• Fluoroquinolone antibiotics
• Penicillamine

Question 17

Contraindications of saliva substitute

Answer 17

-

Question 18

Short term constipation treatment

Answer 18

• Osmotic laxatives (magnesium hydroxide, lactulose, polyethylene glycol)

Question 19

Senna AE

Answer 19

• GI (diarrhea, abdominal cramping, nausea)
• CNS (dizziness, headaches, weakness)
• Sweating, palpitations, flushing, fainting
• Cathartic dependence

Question 20

Loperamide mechanism of action

Answer 20

• Direct action on muscles of GI tract