Gastro - Pharmacology Flashcards
Proton pump inhibitors work on pumps that exchange which two ions?
Hydrogen and potassium
H2-blockers work on which stomach cell type?
Parietal cells
Muscarinic antagonists work on which two cell types in the stomach?
Enterochromaffin-like cells (with M1receptors) and parietal cells (with M3 receptors)
Why are misoprostol, sucralfate, and bismuth beneficial in treatment of gastric ulcers?
These drugs have a protective effect on the mucosa underlying ulcers
Give four examples of H2-blockers.
Cimetidine, ranitidine, famotidine, and nizatidine (remember: Take H2-blockers before you DINE)
What substance is the endogenous agonist of the H2-receptor?
Histamine
What is the effect of H2-blockers on parietal cells?
Reversible decrease of hydrogen ion secretion
List three clinical uses of H2-blockers.
Peptic ulcer, gastritis, mild esophageal reflux
Which H2-blocker has important toxicities that are not seen with other H2-blockers?
Cimetidine
Cimetidine is a potent _____ of P450.
Inhibitor
What effect does cimetidine have on the kidneys?
Decreased creatinine excretion
Which two H2blockers can decrease the renal excretion of creatinine?
Ranitidine and cimetidine
Which adverse effects of cimetidine are seen specifically in males?
Prolactin release, gynecomastia, impotence, decreased libido
By what mechanism does cimetidine cause confusion, dizziness and headaches?
It is able to cross the blood-brain barrier
True or False? Cimetidine is safe during pregnancy.
False; cimetidine crosses the placenta
Give at least two examples of proton pump inhibitors.
Omeprazole and lansoprazole
Proton pump inhibitors work by inhibiting _____ _____ _____ in stomach parietal cells.
Hydrogen potassium adenosine triphosphatase
What are the clinical indications for use of proton pump inhibitors?
Peptic ulcers, gastritis, esophageal reflux, and Zollinger-Ellison syndrome
What is the mechanism of action of bismuth and sucralfate?
They provide a physical barrier in ulcers to protect from stomach acid
What are two of the infectious indications for bismuth or sucralfate?
Traveler’s diarrhea, Helicobacter pylori infection (as part of triple therapy)
What are the three components of triple therapy?
Metronidazole, bismuth, and amoxicillin or tetracycline
True or False? A proton pump inhibitor can also be used when treating an ulcer caused by Helicobacter pylori infection.
True (remember: Please MAke Tummy Better for drugs used to treat Helicobacter pylori infection: proton pump inhibitor, metronidazole, amoxicillin, tetracycline, bismuth)
Misoprostol is a _____ ____ analogue.
Prostaglandin E1
Misoprostol functions by increasing the production and secretion of the _____ _____ _____ and decreasing the production of _____.
Gastric mucous barrier; acid
A woman with rheumatoid arthritis was recently started on misoprostol because of adverse effects of her arthritis medicine. What is the adverse effect and the medication that caused it?
Peptic ulcers induced by nonsteroidal antiinflammatory drugs
A neonate becomes cyanotic on the third day of life despite 100% supplemental oxygen administration. The attending orders infusion of a medication and the neonate’s oxygen saturation slowly returns to normal. What medication did the attending order and how does it improve the cyanosis?
Misoprostol; it maintains the patent ductus arteriosus thereby allowing mixing of pulmonary and systemic circulation in the case of congenital heart disease