Acid-Controlling Drugs Chapter 50 - Acid related pathophysiology o The stomach secretes: Hydrochloric acid (HCl)  digest Bicarbonate  buffer to keep acid from getting too strong  Pepsinogen  proteins Intrinsic factor  vitamin b12 Mucus  protective of the lining of the stomach  Prostaglandins  anti-inflammatory affect- Cells of the Gastric Glando Parietal Produce and secrete HCl Primary site of action for many of the drugs used to treat acid-related disorderso Chief  Secrete pepsinogen, a proenzyme Pepsinogen becomes pepsin when activated by exposure to acid Pepsin breaks down proteins (proteolytic)o Mucous  Mucus-secreting cells (surface epithelial cells) Provide a protective mucus coat  Protect against self-digestion by HCl and digestive enzymes- Acid-Related Diseaseso Helicobacter pylori (H. pylori) Bacterium found in GI tract of 90% of patients with duodenal ulcers and 70% of those with gastric ulcers First-line therapy includes a 10- to 14-day course of a proton pump inhibitor and antibiotics- Types of Acid-Controlling Drugso Antacids Basic compounds used to neutralize stomach acid Salts of aluminum, magnesium, calcium, and/or sodium Many antacid preparations also contain the antiflatulent (antigas) drug simethicone (anti flatulent) o Aluminum salts o Have constipating effectso Often used with magnesium to counteract constipationo Often recommended for patients with renal disease (more easily excreted)o Aluminum carbonate: Basaljel (kidney faliure patients)o Hydroxide salt: AlternaGELAcid-Controlling Drugs o Combination products (aluminum and magnesium): Gaviscon, Maalox,Mylanta, Di-Gelo Magnesium Saltso Commonly cause diarrhea; usually used with other drugs to counteract this effecto Dangerous when used with renal failure—the failing kidney cannot excrete extra magnesium, resulting in accumulationo Commonly cause diarrhea; usually used with other drugs to counteract this effecto Dangerous when used with renal failure—the failing kidney cannot excrete extra magnesium, resulting in accumulationo Calcium Saltso Many forms, but carbonate is most commono May cause constipation, kidney stoneso Also not recommended for patients with renal disease—may accumulate to toxic levelso Long duration of acid action—may cause increased gastric acid secretion (hyperacidity rebound  month to regulate)o Often advertised as an extra source of dietary calciumo Example: Tums (calcium carbonate)o Sodium Bicarbonate o Highly solubleo Buffers the acidic properties of HClo Quick onset, but short durationo May cause metabolic alkalosis (everyday)o Sodium content may cause problems in patients with heart failure, hypertension, or renal insufficiency o H2 antagonists Reduce acid secretion All available over the counter in lower dosage forms Most popular drugs for treatment of acid-related disorders- cimetidine (Tagamet) - nizatidine (Axid)- famotidine (Pepcid) – most common- ranitidine (Zantac) – most commono Proton pump inhibitors The parietal cells release positive hydrogen ions (protons) during HCl production This process is called the proton pump H2 blockers and antihistamines do not stop the action of this pump Drugs:- lansoprazole (Prevacid)Acid-Controlling Drugs - omeprazole (Prilosec)- rabeprazole (AcipHex)- pantoprazole (Protonix) – hospital environment - esomeprazole (Nexium)- Antiflatulents: used to relieve the painful symptoms associated with gaso Simethicone - Miscellaneous Acid-Controlling Drugso sucralfate (Carafate) Cytoprotective drug Used for stress ulcers, peptic ulcer disease Attracted to and binds to the base of ulcers and erosions, forming a protective barrier over these areas Protects these areas from pepsin, which normally breaks down proteins (making ulcers worse) Little absorption from the gut May cause constipation, nausea, and dry mouth May impair absorption of other drugs—give other drugs at least 2 hours before sucralfate Do not administer with other medications Binds with phosphate; may be used in chronic renal failure to reduce phosphate levelso misoprostol (Cytotec) Prostaglandin E analog Prostaglandins have cytoprotective activity Protect gastric mucosa from injury by enhancing local production of mucus or bicarbonate Promote local cell regeneration Help to maintain mucosal blood flow Used for prevention of NSAID-induced gastric ulcers Doses that are therapeutic enough to treat duodenal ulcers often produce abdominal cramps, diarrheao simethicone (Mylicon) Only use this for gas  Antiflatulent drug Used to reduce the discomforts of gastric or intestinal gas (flatulence) Alters elasticity of mucus-coated gas bubbles, breaking them into smaller ones Result is decreased gas pain and increased expulsion via mouth or rectum- Nursing Implications: Antacids o Assess for allergies and preexisting conditions that may restrict the use of antacids, such as: Fluid imbalancesAcid-Controlling Drugs  Renal disease GI obstruction Heart failure (HF) Pregnancyo Patients with heart failure or hypertension should not use antacids with high sodium contento Use with caution with other medications because of the many drug interactionso Most medications should be administered 1 to 2 hours after an antacido Antacids may cause premature dissolving of enteric-coated medications, resulting in stomach upset- Nursing Implications: H2 Antagonistso Assess for allergies and impaired renal or liver functiono Use with caution in patients who are confused, disoriented, or elderlyo Take 1 to 2 hours before antacidso For intravenous doses, follow administration guidelines- Nursing Implications: Proton Pump Inhibitorso Assess for allergies and history of liver diseaseo Not all are available for parenteral administrationo May increase serum levels of diazepam and phenytoin; may increase chance for bleeding with warfarinAcid-Controlling Drugs Questions1. A patient who has chronic renal failure wants to self-treat with an antacid for occasional heartburn. Which medication is the best choice for this patient?A. A magnesium-containing antacidB. A calcium-containing antacidC. An aluminum-containing antacidD. Because of renal problems, the patient should not take antacids for this problem.Rationale: Aluminum- and sodium-based antacids are recommended for patients with renal compromise because they are more easily