Anti-ulcer drugs Flashcards
Cimetidine, Famotidine, Nizatidine, and Ranitidine make up what class of medication?
Histamine (H2) Receptor Antagonists
Some of the H2 receptor antagonists are made with?
Antacids including calcium/magnesium
Where do H2 receptor antagonists act on?
Basolateral membrane of parietal cell
How long is the onset of action for H2 receptor antagonists?
How does this compare to antacids and PPIs?
How long does it take ulcers to heal?
Does it completely inhibit all acid production?
1) 0.5 to 2 hours
2) Longer than antacids, shorter than PPIs
3) 4-8 weeks
4) No, it only inhibits about 20-50%
Which H2 receptor antagonists adverse effect decreases testosterone binding to androgen receptor?
How does this affect men and women?
1) Cimetidine
2) Gynecomastia in men and galactorrhea in women
Why does cimetidine have a lot of drug-drug interactions?
Because it is a prototypical inhibitor of several CYP450 isoenzymes
Which H2 receptor antagonists should be used during pregnancy only if necessary?
Ranitidine and Famotidine
Lansoprazole, Dexlansoprazole, Omeprazole, Esomeprazole, Pantoprazole, and Rabeprazole make up what class of medication?
Proton Pump Inhibitors (PPIs)
What is the MOA of PPIs?
How long does it take to create a new steady state of pump activity?
1) Binds to sulfhydryl groups of H+/K+- ATPase at parietal cell secretory sites, thereby inhibiting gastric acid secretion
2) Several days
How long does it take for full symptom effects with PPIs?
How does this compare to H2 antagonists?
Does it completely inhibit all acid production?
How long does it take ulcers to heal?
1) Several days
2) Takes longer
3) Comes very close to it (up to 90%)
4) 4-8 weeks
What serious adverse effect can PPIs cause?
CDAD (Clostridium Difficile-Associated Diarrhea)
Why does omeprazole have a lot of drug-drug interactions?
Because it is a prototypical PPI for CYP450 inhibition
Which PPI should be used during pregnancy only if necessary?
Lansoprazole and pantoprazole
Sucralfate makes up what class of medications?
Surface Acting Agents
What is sucralfate made up of chemically?
An octasulfate of sucrose with Al(OH)3 added
What is the MOA for sucralfate?
What does it ultimately prevent?
What was Dr. Segars analogy of this to help cement its MOA?
1) Undergoes cross-linking due to stomach acid which creates a viscous, sticky polymer that adheres to epithelial cells around the ulcer
2) Prevents acid access to ulcer sites
3) It is the band-aid drug
How long should sucralfate be used for?
Short term therapy
What may sucralfate also stimulate?
What effect do the stimulated substances have?
How does it affect pH?
1) Local prostaglandin and mucus production and epidermal growth factor
2) Cytoprotection
3) It doesn’t
What site is sucralfate indicated for?
Can it be used for ulcers in other regions?
1) Duodenal ulcers
2) Yes
Why can sucralfate cause constipation or severe renal failure?
Because it contains aluminium
Because of possible drug interactions when should sucralfate be taken?
How is it dosed for active ulcers?
1) Two hours after other meds
2) QID
Misoprostol makes up what class of medications?
PGE1 Analog
What is the MOA of misoprostol?
Provides protective prostaglandin to gastric mucosa and reduces gastric acid release from parietal cell
How does misoprostol provide cytoprotection?
1) Stimulates bicarbonate and mucous production
2) Increases mucosal blood flow