Which pharmacological age-related principle is important when administering medications to elderly clients?

• A. Gastric pH is often decreased in the elderly.
• B. Decreased cardiac output increases the risk for adverse drug reactions.
• C. Mucosal edema can increase the absorption of drugs.
• D. Drugs administered intravenously have a faster absorption rate than oral drugs.

Answer: (B)

In older adults, reduced cardiac output means less blood flow to vital organs like the liver and kidneys, which are central to drug metabolism and excretion. When these organs receive less perfusion, drugs are cleared more slowly and may not be distributed or eliminated as efficiently. That can lead to higher and more prolonged drug exposure, increasing the risk of adverse drug reactions. Because aging often comes with polypharmacy and heightened sensitivity to medications, this concept explains why elderly patients require careful dosing, slower titration, and close monitoring for toxicity.

Other statements don’t fit aging physiology as well. Gastric pH in older adults tends to be less acidic (pH can rise), not decreased; mucosal edema isn’t a standard, universal age-related absorption change; and while intravenous administration bypasses absorption, the question centers on age-related changes in pharmacokinetics and safety—not just route-specific absorption differences.