Medication Errors Disproportionately Affect Vulnerable Populations

The National Coordinating Council for Medication Error and Prevention defines a medication error as “any preventable event that may cause or lead to inappropriate medication use or patient harm while the medication is in the control of the health care professional, patient, or consumer. Such events may be related to professional practice, health care products, procedures, and systems, including prescribing, order communication, product labeling, packaging and nomenclature, compounding, dispensing, distribution, administration, education, monitoring, and use."¹

According to the CDC, more than 1.5 million people visit the emergency department every year in the United States due to medication errors. Almost 500,000 people require hospitalization.² In the United States, medication errors lead to between 44,000 and 98,000 hospital deaths every year, which is more than the number of deaths from motor vehicle accidents. These events are estimated to cost between $37.6 billion and $50 billion in health care costs, disability, and lost productivity.³

Pediatric patients, older patients, and those with low health literacy are especially vulnerable to medication errors and adverse effects. This is due to a combination of physiological differences, cognitive challenges, complex medication regimens, and communication barriers.

Pediatric Patients

Children are not small adults and are highly vulnerable to medication errors and adverse effects. Pediatric patients have distinct physiology, developmental changes, and complexities in medication practices that require careful consideration.

Physiological and developmental factors are unique in this population. Because children undergo continuous maturation throughout childhood, their evolving physiology affects the pharmacokinetics and pharmacodynamics of medications.^4,5 As a result, data from adults cannot be easily extrapolated to children.

Dosing can also be challenging due to children’s small body mass, which often requires specialized formulations and calculations based on body weight, height, age, and clinical condition. These factors introduce greater variability and contribute to an increased risk of error.⁶

In addition, children are fully dependent on caregivers for medication, which places them at higher risk for medication errors. Mistakes are more common in infants and toddlers than in older children, and those with chronic conditions requiring polypharmacy also have an increased risk. Approximately 30% to 80% of pediatric medication errors occur at home.⁷

Children also cannot often effectively communicate about their symptoms, leaving caregivers and providers to determine which medication may be appropriate. Similarly, their limited ability to verbalize how a medication is affecting them can delay the detection of medication errors.

Older Patients

Older patients are highly vulnerable to medication errors for a variety of reasons, including physiological changes, polypharmacy and comorbidities, cognitive decline, and transitions of care. This can lead to serious, sometimes fatal consequences.

Physiological changes are particularly notable in older adults. Older patients often experience decreased liver function, which decreases the metabolism of medication, leading to longer drug half-lives. Kidney function also decreases, reducing the excretion of medication, thereby leading to an accumulation of medication in the system. Additionally, total body water decreases with age due to muscle loss and fat gain, so water-soluble medications reach higher concentrations and fat-soluble medications accumulate.⁸

Polypharmacy, defined as the regular use of 5 or more medications at the same time, is common in older patients. Aging patients also often experience multiple chronic health conditions, each with their own set of symptoms and treatments. This increases the risk of medication errors and adverse effects, especially cumulative effects and drug interactions.⁹

Cognitive changes in older patients significantly increase the risk of medication errors. As memory and recall fade, patients may forget they have already taken a dose of their medication, leading to duplication or forgotten instructions. Cognitive decline impairs the ability to manage medications and track schedules. The ability to understand directions may also diminish, leading to confusion about dose and frequency.¹⁰

Finally, older patients, particularly ones with several comorbidities, often undergo transitions of care from one health care setting to another. It is estimated that 60% of medication errors occur during transitions of care, and sharing information among multiple care teams may introduce a wide range of errors.¹¹

Limited Health Literacy and Language Proficiency

Limited health literacy and language barriers increase the risk of medication errors by hindering communication between patients and health care providers. Health literacy is a person’s ability to find, understand, and use health information to make decisions.¹² Complex dosing instructions, such as a tapering dose of steroids, can lead to confusion, and individuals with inadequate health literacy are likely to overlook crucial warnings.¹³ Unfortunately, patients may be embarrassed to admit they do not understand the medication information.

Language barriers significantly affect the therapeutic relationship between the patient and the health care provider due to the inability to explain their health condition and symptoms and the lack of understanding of medication information. This can result in medication errors, poor patient outcomes, and a strain on the health care system, highlighting the importance of translators and materials in multiple languages.¹⁴

Impact of Medication Errors

Medication errors have severe consequences for the patient as well as the health care system and the pharmacist.

For the patient, medication errors can range from mild discomfort to severe injury, life-changing complications, or even death. Medication errors erode patient trust and can cause significant psychological distress.³

In addition to the erosion of patient trust, medication errors strain the health care system and increase health care costs through extended hospital stays, additional treatments, and readmissions. They can also lead to legal liabilities and damage institutional reputations.

Pharmacists can also face significant personal and professional repercussions from medication errors. These can include emotional and psychological trauma, leading to feelings of guilt, self-doubt, and anxiety. Additionally, pharmacists may endure disciplinary action from licensing boards, legal action, and even criminal charges.

Conclusion

Across all vulnerable populations—pediatric, older, and those with low health literacy—medication errors are driven by a convergence of patient-specific vulnerabilities and have far-reaching consequences. Although each group faces unique challenges, the underlying reasons for errors share a common thread: communication failures, cognitive barriers, and the complexities of modern health care. Pharmacists play a critical role in mitigating these risks by providing clear counseling, tailoring communication to patient needs, and implementing safety checks that help prevent errors before they reach the patient.

About the Author

Kathleen Kenny, PharmD, RPh, earned her doctoral degree from the University of Colorado Health Sciences Center in Aurora. She has more than 30 years of experience as a community pharmacist and works as a clinical medical writer based in Albuquerque, New Mexico.

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