• The Impact of Aging on Pharmacokinetics: Implications for Medication Management in Elderly Patients
  • Amir Hossein Ghorbani Pour Mohammadi,1,* Saba Rahimi,2
    1. Department of quantum and converging science Branch, Tehran Islamic Azad University, Tehran, Iran
    2. Department of quantum and converging science Branch, Tehran Islamic Azad University, Tehran, Iran


  • Introduction: The aging process leads to significant physiological changes that affect how medications are absorbed, distributed, metabolized, and excreted—collectively known as pharmacokinetics (ADME). Acknowledging these changes is crucial for optimizing drug therapy in elderly patients, who often contend with multiple health conditions and are prescribed various medications. By understanding these transformations, healthcare providers can improve treatment outcomes and enhance the quality of care for older adults.
  • Methods: A thorough review of the literature was performed utilizing databases such as PubMed and various academic journals that concentrate on pharmacokinetics in older populations. The keywords employed in the search included "aging," "pharmacokinetics," "drug metabolism," and "elderly." Studies published between 1990 and 2023 were selected for analysis to provide an overview of how aging affects pharmacokinetic processes.
  • Results: The review highlighted several significant pharmacokinetic changes linked to aging: Absorption: While the overall absorption of drugs tends to remain consistent in healthy older adults, factors such as lower gastric acidity and delayed gastric emptying can influence the absorption rates of certain medications. Distribution: An increase in body fat and a decrease in lean muscle mass lead to a larger volume of distribution for lipophilic drugs, which results in longer half-lives. Conversely, hydrophilic drugs experience a smaller volume of distribution. Metabolism: Age-related changes often result in reduced hepatic metabolism due to decreased liver size and blood flow. This reduction particularly affects the clearance of drugs that have high hepatic extraction ratios. Excretion: Renal function generally declines with age, impacting the elimination processes for drugs primarily excreted by the kidneys. This necessitates vigilant monitoring and possible dosage adjustments to prevent adverse effects.
  • Conclusion: Aging-related alterations in pharmacokinetics have significant clinical implications for managing medications in older adults. These changes result in increased variability in individual drug responses, underscoring the necessity for a cautious prescribing strategy. The guideline of "start low, go slow" is particularly relevant for this age group, as it aids in minimizing adverse reactions and improving treatment outcomes.
  • Keywords: Aging, pharmacokinetics, drug metabolism, renal function, elderly care