Pharm110 Chp 24 Hyperacidity and GERD agents Flashcards
Secretory functions of the stomach lining
- Parietal cells (secrete hydrochloric acid “HCI”
- Chief cells (secrete pepsinogen, inactive form of pepsin, needs to combine with HCI to be come active)
- Mucoid cells (secrete mucus)
Stomach Hyperchlorhydria
Acid reflux produced from
- Eating high fat meals
- Increased alcohol intake
- Emotional turmoil
Goal of Antacid therapy
- Neutralize acid
- Inhibit pepsin activity
- Increase resistance of the stomach lining
- Increase tone of the LES lower esophageal sphincter
Types of antacids
3 forms
- Magnesium (diarrhea)
- Aluminum (constipation)
- Calcium (constipation)
Action
- Neutralize gastric acidity
- Low doses promote gastric mucosal defensive mechanisms
Systemic antacids
e.g. Sodium Bicarbonate
Action
- Short term therapy
- Rapid onset (highly gastric soluble)
Adverse effects
- Rebound hyperacidity
- Prolonged use causes an overload on the kidneys due to high concentration of absorbed electrolyte.
Nonsystemic actacids
e.g. Calcium carbohydrate (Tums, Rolaids), Aluminum carbonate (Basaljel), Magaldrate (Riopan)
Action
- Long term therapy (most of dose remains in GI tract)
- Will not alter acid base balance
Adverse effects
- Magnesium accumulation may be toxic in renal impaired clients.
- Aluminum hydroxide has been associated with phosphate depletion.
Antacid interactions
- Binding of other drugs to antacids reduces availability of other drugs to the client (tetracyclines and sucralfate)
- Chemical inactivation due to increase of gastric pH (digoxin, chlorpromazine, isoniazid, and phenytoin)
- Increase absorption of others (salicylates and levodopa)
- Increase stomach and urine pH (alkaline), decreases absorption and excretion of certain drugs (salicylates and barbiturates)
Antacids and other drugs should not be taken within 1-2 hours of each other to prevent interactions.
Nursing interventions for antacids
Monitor for adverse effects
- N/V/D, abdominal pain
- Constipation, acid rebound
Monitor for therapeutic response
-Notify Dr. if symptoms are not relieved
Client teaching
- Maintain schedule of antacid admin
- Shake all liquids, and follow tablets with water
- Avoid aspirin, ibuprofen and naproxen in clients with peptic ulcer disease
- Avoid simultaneous admin of antacids and antibiotics
H2 Histamine receptor antagonists
Prefix “dine”
e.g. Cimetadine (Tagament), Famotidine (Pepcid), Nizatidine (Axid), Ranitidine (Zantac)
Action
- Treat Duodenal ulcers and gastric ulcers
- Inhibit Histamine on H2 receptors of parietal cells (reduced gastric acid secretion) allowing ulcers to heal
Adverse effects
- Diarrhea
- Muscle pain
- Rash
- Drowsiness
- Confusion
- Not recommended for nursing mothers or children under 16
Cimetidine is only one to cause antiandrogenic effects (impotence, gynecomastia)
-Increase toxicity of many other drugs.
Proton pump inhibitors
Prefix “zole”
e.g. Omeprazole (Prolosec), Esomeprazole magnesium (Nexium), Lansoprazole (Prevacid), Rabeprazole (Aciphex), Pantoprazole (Protonix)
Action
- Blocks final step of acid production in the stomach (H+ - K+ ATPase enzyme from converting H+ + Cl+ into HCL)
- For clients with GERD and gastric hypersecretory condition.
Adverse effect
-Causes Warfarin (anticoagulant) action to be increased
Indicated in combination with clarithromycin and amoxicillin to treat Helicobacter pylori infections.
Metoclopramide (Reglan)
Action
- Stimulates motility of upper GI tract without stimulating the production of gastric, biliary, or pancreatic juices.
- Relaxes pyloric sphincter, increases peristalsis in duodenum and jejunum without effecting motility of the large intestine.
- Increases LES pressure, decreasing likelihood of GERD.
Adverse effects
- Produces extrapyramidal effects (Parkinson like symptoms)
- CNS depression
- GI upset
Helicobacter Pylori
Organism associated with development of peptic ulcer disease
Treatment
-Metronidazole (Flagyl), antiprotozoal agent along with Bismuth Subsalicylate (Pepto-Bismol) and Tetracycline (antimicrobial agent) for 4 weeks to eradicate H. Pylori.
Sucralfate
Chemical derivative of sucrose
Action
- Treat duodenal ulcers
- Appears to combine with protein at affected site to form a band aid complex that covers the ulcer and protects it from further attack by acid, pepsin and bile salts.
Misoprostol (cytotec)
Synthetic prostaglandin compound, decreases gastric acid secretion
Action
-Prevention of gastric ulcers produced by NSAIDs such as Aspirin, indomethacins and other prostaglandin synthesis inhibitors
Adverse effect
-Cause uterine contractions and cause miscarriage in pregnant women
Pancreatic Enzymes
Pancrelipase and pancreatin are required for proper digestion of fats, proteins and complex carbohydrates.
Pts. with pancreatic disease may be deficient in the these enzymes and require a supplement.
Viokase is available
Possible hypersensitivity due to derived from pigs or cows.
