Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
GERD & PUD drugs
Drugs for treating GERD, peptic ulcer disease, etc
| Question | Answer |
|---|---|
| What are the 3 main type of epithelial cell types in the stomach? | Chief cells, parietal cells, mucus neck cells |
| Parietal cells secrete... | Hydrochloric acid |
| Mucus neck cells secrete... | Bicarbonate and mucus |
| Chief cells secrete... | Pepsinogens, which are converted to pepsin which digests proteins to amino acids |
| What are the 3 main endocrine cell types in the stomach? | Enterochromaffin-like (ECL) cells, G cells, and D cells |
| ECL cells synthesize and secrete... | Histamine |
| G cells synthesize and secrete... | Gastrin |
| D cells synthesize and secrete... | Somatostatin |
| These two hormones/substances directly stimulate the parietal cells to secrete acid | ACH (from the vagus nerve) & Histamine (from ECL cells) |
| These two hormones/substances indirectly stimulate the parietal cells to secrete acid | ACH (from the vagus nerve)and gastrin(from G cells) stimulate ECL cells to release histamine, which stimulates parietal cells to release HCl (acid). |
| What hormones/substances inhibits acid secretion? | Somatostatin (directly), secretin (indirectly, it inhibits gastrin), PGE2, CCK. |
| What stimulates somatostatin release? | HCl (acid) |
| What receptor do gastrin bind to on ECL and parietal cells? | ECL & Parietal cell: CCK-B receptor |
| What receptors do ACh bind to on ECL and parietal cells? | ECL: an unknown muscarinic receptor Parietal cell: M3 muscarinic receptor |
| What receptor does histamine bind to on the parietal cell? | H2 |
| This hormone-like substance also binds to the parietal cell and inhibits acid secretion | Prostaglandin E2; it binds to the PG receptor |
| Antisecretory drugs | Histamine H2 Receptor Antagonists & Proton Pump (H+,K+-ATPase) Inhibitors |
| Names of H2 Histamine Receptor Antagonists | Cimetidine, Ranitidine, Famotidine, and Nizatidine |
| Long-term high dosage therapy with Cimetidine can cause these adverse effects: | Loss of libido, impotence, and gynecomastia; Because Cimetidine enhances prolactin secretion, inhibits metabolism of estradiol, and binds to androgen receptors |
| Drug interactions of Cimetidine | It inhibits cytochrome P450, thus it slows down the metabolism of other drugs |
| H2 blockers compared to Proton Pump Inhibitors (PPIs) | PPIs work better, they suppress gastric acid much more strongly than H2 receptor antagonists; they have a short half-life but long duration of action |
| Proton Pump Inhibitors | Are prodrugs; are activated in acidic pH; the active drug accumulates in parietal cells; bind to H+, K+-ATPase (proton pump) from the luminal side; bind to proton pump irreversibly (which leads to their long duration of action) |
| PPI MOA | They are absorbed from the intestine into the blood stream; they enter parietal cell then move into the canaliculi (high acidity compartment); are converted into active form (protonated); act on H+, K+-ATPase from luminal side; irreversibly binds |
| What keeps PPIs from being activated in the stomach? | An enteric coating that's removed in the intestines |
| PPI distribution and clearance | They're only distributed to active parietal cells; only bind to active proton pumps; relatively fast clearance from the blood |
| PPI administration | A single oral dose prior to the first meal of the day in the morning (b/c in the morning there is hunger from overnight fasting, and thus many parietal cells activated); Need 7 days to become fully effective |
| Names of PPIs | Omeprazole, Lansoprazole, Rabeprazole, and Pantoprazole, Esomeprazole (S-form of omeprazole) and Dexlansoprazole (D-form of lansoprazole) |
| PPI therapeutic use | Used to treat gastric/duodenal ulcers, GERD, and Zollinger-Ellison syndrome |
| Omeprazole vs Esomeprazole | Esomeprazole has a longer half-life (1.5 hrs) than Omeprazole (0.5 hrs) due to slower metablism of Esomeprazole. |
| Prokinetic drugs | Accelerate gastric emptying and increase the pressure of lower esophageal sphincter (LES). Example: Metoclopramide |
| Therapeutic use of Metoclopramide | Diabetic gastroparesis and esophageal reflux; nausea and vomiting due to various causes including cancer chemotherapy |
| Actions of Metoclopramide | An agonist at the serotonin 5-HT4 receptor (enhances the release of myenteric ACh and increases G.I. motility); an antagonist at the dopamine D2 recptor (increases G.I. motility and has an antiemetic effect; also a weak 5-HT3 antagonist (antiemetic) |
| Adverse effects of Metoclopramide | Extrapyramidal symptoms (extreme restlessness, involuntary movements, tardive dyskenesia, dystonia, tremors); hyperprolactinemia, anxiety, depression, drowsiness, etc. |
| A prostaglandin analog drug | Misoprostol |
| Actions of Misoprostol | Enhances mucus and HCO3- secretion and inhibits gastric acid secretion |
| Therapeutic uses of Misoprostol | Prevents NSAIDs-induced ulcer |
| Adverse effects of Misoprostol | Diarrhea, abdominal cramps, spontaneous abortion |
| Heals peptic ulcers | Antacids, H2 blockers, and PPIs |
| Potential problems associated with PUD treatment | Possible hypergastrinemia, which can lead to acid rebound; relapse of the disease upon termination of drugs |
| How can H. Pylori survive in the acidic environment of the stomach | H. pylori can convert urea into ammonia to form a protective later. It also converts urea into bicarb. |
| H. pylori breath test | The bicarb created by H. pylori goes into the blood stream and is converted to CO2 by the lungs. This leads to an increase in CO2 exhaled, which can be detected by breath test. |
| Regimens for eradicating H. Pylori | Dual therapy: antibiotic plus anti-secretory drug Antibiotic therapy |
| Drugs used in Dual therapy for H. pylori | Antibiotic: Amoxicillin or Clarithromycin Antisecretory drugs: H2 blocker and PPI |
| Drugs used for Antibiotic therapy for H. pylori | Metronidazole, Bismuth compound, and either Tetracycline or Amoxicillin |
Created by:
MarcoB78
Popular Pharmacology sets