Drugs Acting on the Gastrointestinal System Flashcards
1
Q
Drugs used to treat Gastroesophageal Reflux Disease (GERD) and Ulcer Disease
A
- Histamine-2 Antagonists: block the release of hydrochloric acid in response to gastrin.
- Antacids: interact with acids at the chemical level to neutralize them.
- Proton Pump Inhibitors: suppress the secretion of hydrochloric acid into the lumen of the stomach.
- GI Protectant: coat any injured area in the stomach to prevent further injury from acid.
- Prostaglandin: inhibit the secretion of gastrin and increase the secretion of the mucous lining of the stomach, providing a buffer.
2
Q
Histamine-2 Antagonists
definition
A
- Selectively block H2 receptors located on parietal cells—this prevents the release of gastrin (a hormone that causes local release of histamine, due to stimulation of histamine receptors, blocking the production of hydrochloric acid.
- This action also decreases pepsin production by the chief cells.
- H2 receptor sites are also found in the heart, and high levels of these drugs can produce cardiac arrhythmias.
3
Q
Histamine-2 Antagonists
list medications
A
- Cimetidine (Tagamet, Tagamet HB) P
- Famotidine (Pepcid, Pepcid AC)
- Nizatidine (Axid)
- Ranitidine (Zantac)
4
Q
Histamine-2 Antagonists
usual indications
A
- Short-term treatment of active duodenal ulcer or benign gastric ulcer
- Treatment of pathological hypersecretory conditions such as Zollinger-Ellison syndrome.
- Prophylaxis of stress-induced ulcers and acute upper GI bleeding in critical patients.
- Treatment of erosive gastroesophageal reflux.
- Relief of symptoms of heartburn, acid indigestion, and sour stomach (OTC preparations).
5
Q
Histamine-2 Antagonists
adverse effects
A
can include:
- dizziness
- confusion
- cardiac arrhythmias
- galactorrhea
6
Q
Antacids
definition
A
-chemically react with and neutralize acid in the stomach, providing rapid relief from increased acid levels.
7
Q
Antacids
list medications
A
- Aluminum salts (AlternaGEL)
- Calcium salts (Oystercal, Tums)
- Magaldrate (Losopan, Riopan)
- Magnesium salts (Milk of Magnesia, others)
- Sodium bicarbonate (Bell/ans) P
8
Q
Antacids
usual indications via individual medication
A
- Aluminum salts: symptomatic relief of GI hyperacidity; treatment of hyperphosphatemia; prevention of formation of phosphate urinary stones.
- Caclium salts: symptomatic relief of GI hyperacidity; treatmenet of Ca deficiency; prevention of hypocalcemia.
- Magaldrate: Symptomatic relief of GI hyperacidity in adults.
- Magnesium salts: Symptomatic relief of GI hyperacidity; prophylaxis of stress ulcers, relief of constipation.
- Sodium bicarbonate: Symptomatic relief of GI hyperacidity; minimization of uric acid crystalluria, adjunctive treatment in severe diarrhea.
9
Q
Proton Pump Inhibitors
definition
A
- Suppress gastric acid secretion by specifically inhibiting the hydrogen-potassium adenosine triphosphatase (H+, K+-ATPase) enzyme system on the secretory surface of the gastric parietal cells.
- This action blocks the final step of acid production, lowering the acid levels in the stomach.
10
Q
Proton Pump Inhibitors
list medications
A
- Dexlansoprazole (Kapidex)
- Esomeprazole (Nexium)
- Lansoprazole (Prevacid)
- Omeprazole (Prilosec) P
- Pantoprazole (Protonix)
- Rabeprazole (Aciphex)
11
Q
Proton Pump Inhibitors
usual indications
A
- short-term treatment of active duodenal ulcers, GERD, erosive esophagitis, and benign active gastric ulcer.
- long-term treatment of pathological hypersecretory conditions
- maintenance therapy for healing of erosive esophagitis and ulcers
- in combination with amoxicillin and clarithromycin for the treament of H. pylori infection.
12
Q
GI Protectants (definition)
A
- coat any injured area in the stomach to prevent further injury from acid.
- Sucralfate forms an ulcer-adherent complex at duodenal ulcer sites, protecting the sites against acid, pepsin, and bile salts.
- This action prevents further breakdown of the area and promotes ulcer healing.
- Also inhibits pepsin activity in gastric juices, preventing further breakdown of proteins in the stomach, including the protein wall of the stomach.
13
Q
GI Protectants
list medications
A
- Sucralfate (Carafate) P
14
Q
Prostaglandins
definition
A
- used to protect the stomach lining.
- Prostaglandin E1 inhibits gastric acid secretion and increases bicarbonate and mucous production in the stomach, thus protecting the stomach lining.
15
Q
Prostaglandins
list medications
A
- Misoprostol (Cytotec) P
