What change in pharmacokinetics is increased in geriatric patients?

In geriatric patients, the percentage of body fat generally increases due to age-related changes in body composition. As individuals age, there is often a decrease in lean body mass and total body water, while the percentage of body fat rises. This change in body composition can significantly impact the pharmacokinetics of medications.

For instance, many medications are lipophilic (fat-soluble) and can have an increased volume of distribution in patients with higher body fat, leading to prolonged half-lives and a potential for accumulation. Consequently, adjustments in dosage may be necessary to avoid toxicity or adverse drug reactions in geriatric patients with higher fat percentages.

In contrast, blood volume typically decreases with age, renal clearance often declines, and liver size may also decrease, which does not align with the question regarding what changes are increased in geriatric patients. Understanding these pharmacokinetic changes is crucial for safe and effective medication management in the older population.