Upper and Lower GI Pharmacology Flashcards
Name the acid controlling drugs (5)
- H2 Receptor Antagonist
- Proton pump inhibitors
- Antacids
- Antibacterial drugs
- Other antiulcer drugs
What is the example drug for H2 Receptor Antagonist drug?
Ranitidine
What is the example drug for PPI? (Proton pump inhibitor)
Omeprazole
What is the example drug for antacids?
Aluminum hydroxide
What are the example drugs for antibacterial drugs? (4)
- Amoxicillin
- Clarithromycin
- Metronidazole
- Tetracycline
What are the example drugs for antiulcer drugs? (2)
- Sucralfate
2. Misoprostol
TRUE or FALSE. H2 Receptor antagonist produces allergy symptoms.
FALSE. H1 receptors produce allergy symptoms not H2 receptors.
Where are the H2 receptors located?
In the parietal cells of the stomach
What happens when you block the H2RA (Histamine-2 Receptor Antagonist) receptors?
Reduces volume of gastric juice and decreases concentration of acid
How can it be administered to the patient?
- PO
- IM (not used a lot)
- IV (urgent)
What are the indications for H2RA?
Healing & Prevention of gastric/duodenal ulcers, treatment of GERD
H2RA is (a) metabolized and (b) excreted by what?
(a) Liver
(b) Kidney
What are the adverse effects of Ranitide?
- CNS; confusion, hallucination, CNS depression (crosses bbb poorly. so this is rare)
- Increased risk for pneumonia (increased pH) - When pH is more basic, it increases bacteria to survive
TRUE or FALSE. Ranitidine commonly have side effects
FALSE. Side effects of Ranitidine are uncommon
What are the contraindications and precautions of Ranitidine? (2)
- Some H2RAs (cimetidine) inhibit hepatic drug-metabolizing enzymes but this effect is minimal with Ranitide. *Dosage may need to be adjusted in drugs with narrow safety margins.
- Antacids slightly decrease absorption of ranitidine (greater effect on cimetidine)
What are other H2RA’s? (3)
Cimetidine (first H2RA, inhibit drug metabolism enzymes), Famotidine, Nizatidine
What are nursing considerations and assessment? (4)
- Assess for epigastric pain or signs of GI bleeding (hematemesis, frank blood or occult blood in stool)
- Assess for signs of confusion (esp. in older adults)
- CBC periodically (rare side effect)
- Administer antacids an hour apart (antacid decrease absorption so you have to take an hour before or after)
What does PPI: Omeprazole cause?
Causes irreversible inhibition of H+, K+ ATPase, the enzyme (ezyme produce H+ but changes to K+) that generates gastric acid
A single dose of PPI: Omeprazole inhibits acid production by what (a) percentage for how (b) long?
(a) 97%
b) 2 Hours - More effective than H2RA (65%
Is the effect of Omeprazole reversible or irreversible and why?
Irreversible. There is no new acid until new enzyme is made which may take days to weeks depending on the person.
What does is it mean when a drug is acid-labile?
Capsules contain enteric coated granules that dissolve in duodenum.
Easily destroyed in an acidic enviroment.
What are the indications of Omeprazole? (3)
Treatment of gastric/dupdenal ulcer, treatment of GERD, prevention of stress ulcers is hospitalized patients
What are the minor adverse effects of Omeprazole? (4)
- Headache
- Diarrhea *
- Nausea
- Vomiting
What are the major adverse effects of Omeprazole?
- Pneumonia ( ^ pH - basic)
- Fractures (decrease in calcium absorption, esp. in older adults)
- Rebound acid (body creates more acid) hyper-secretion (dyspepsia)
- **Hypomagnesemia (decrease Mg absorption with long term use)