NR 565 Final Exam WEEK 7 _ 8 Study Guide

Antacids: weak bases that react with hydrochloric acid to form salt & water. o Used in the treatment of Hyperacidity, GERD, PUD, hyperphosphatemia, and calcium deficiency o Contain combinations of  metallic cation (aluminum, calcium, magnesium, and sodium)  and basic anion (hydroxide, bicarbonate, carbonate, citrate, and trisilicate)  Pharmacodynamics, Pharmacokinetics, Pharmacotherapeutics o Neutralize Gastric Acidity (causes ^pH of the stomach and duodenal bulb) o Inhibit proteolytic activity of pepsin o Increase lower esophageal sphincter tone o Acid-neutralizing capacity ANC varies between products expressed in mEqs o If ingested in a fasting state, antacids reduce acidity for approximately 20 to 40 minutes o If taken 1 hr after a meal, acidity is reduced for 2 to 3 hrs o A second dose taken after a meal maintains reduced acidity for more than 4 hrs after the meal o The action of antacids occurs locally in the GI tract with minimal absorption, minimal metabolism o ALL antacids are contraindicated in the presence of severe abdominal pain of unknown cause, especially if accompanied by fever -HIGH SODIUM content: pts w/ HTN, CHF, marked renal failure, or on low-sodium diets need to use low sodium preparation -Concurrent administration with enteric-coated drugs, destroys the coating= alters absorption, ^ the risk for adverse effects -Administrations should be separated by at least 2 hours to decrease drug/drug interactions 1. Calcium based antacids: TUMS, Caltrate, Calcarb