GI drugs Flashcards
Cimetidine (Tagamet) and famotidine (Pepcid) class and MOA, indications
- H2 rec antagonist
- Block H2 receptors in the stomach and dec gastric acid secretion; inc stomach pH
- GERD, PUD, ulcer prophylaxis (bc aspiration PNA risk–critically ill, ICU), heartburn/dyspepsia
Cimetidine (Tagamet) and famotidine (Pepcid) SE and NC
- Well tolerated, CNS alter in old (LOC, alert), slight inc risk for PNA in old
- PO or IV
- give at least 1h apart from antacids
- cimetidine is CPY450 inhibitors (older agents); Famotidine is NOT
- can inc level warfarin, phenytoin, theophylline
- give IV slow to avoid brady
Omeprazole, pantoprazole, esomeprazole class, indications, and MOA
- PPI
- Bind to proton pump and inhibit the hydrogen K ATPase enzyme system (pump) to irreversibly inhibit secretion of HCl
- short term tx of PUD and GERD
Omeprazole, pantoprazole, esomeprazole SE and NC
Short-term (safe)
Long-term (may inc risk of PNA, bone loss/hip fx, stomach cancer)
- work better than H2RA
- OTC or rx
- benefits outweigh risks often
- few intx
Sucralfate class, indications, and MOA
- mucosal protectant
- duodenal and gastric ulcers
- Alters when exposed to gastric acid and becomes stick, thick gel that makes protective barrier
Sucralfate SE and NC
No major fx, may cause constipation
- always PO tab or suspension
- take before eat
- can dec drug abs (take other drugs first)
- take 2h apart
Antacids MOA and indications
Neutralize gastric acid by 50% by doing chem chx
- PUD, GERD, stress ulcers (prophylaxis), may help with heartburn or indigestion
Antacids SE and NC
Diarrhea (magnesium), constipation (aluminum, Ca)
- rebound effect when stopped
- chelation–bind to other drugs when taken so separate from other drugs by 1-2h
- balanced antacid–Al+Mg (maalox and mylanta)
Ondansetron class, indications, and MOA
- Sr blocker
- N/V (esp chemo)
- Blocks Sr rec in chemoreceptor trigger zone in brain and in afferent vagal nerves in stomach or sm intestine
Ondansetron SE and NC
Mild HA, diarrhea, dizzy, constipation; well tolerated
- PO or IV
- risk Sr syndrome
- careful with SSRIs, SNRIs, TCAs, MAOIs, buspirone, tramadol if daily use
Dimenhydrinate (Dramaine), meclizine, hydroxyzine class, indications, and MOA
- Antihistamines
- tx dizzy and nausea assoc with motion sickness
- Block H1 receptors in inner ear
Dimenhydrinate (Dramaine), meclizine, hydroxyzine SE and NC
Sedation, drowsy, dizzy, anticholinergic
- fall risk bc ACh
- no hydroxyzine IV bc tissue damage, thrombosis, gangrene
Metoclopramide (Reglan) class, indications, and MOA
- Prokinetic agent aka dopamine antagonist
- GERD, diabetic gastroparesis, N/V assoc with chemo/radiation/opioids, GI motility issues (CF), paralytic ileus
- Block dopamine rec, inc tone of lower eso sphincter, inc peristalsis in stomach and int
Metoclopramide (Reglan) SE and NC
Sedation
Severe - extrapyramidal sx EPS), restless, neuroleptic malignant syndrome
- EPS risk when also taking antipsychotics esp or Reglan (drug-induced mvt like akathasia, acute dystonia, parkinsonism, tardive dyskinesia, NEUROLEPTIC MALIGNANT SYNDROME–rigid, fever, drowsy, SZ)
Diphenoxylate with atropine, loperamide class, indications, and MOA
- antidiarrheal
- diarrhea
- dec intestinal peristalsis, dec intestinal effluent