People today are living longer, with most reaching their sixties and beyond. Every country is seeing a rise in the number and proportion of older adults. According to WHO, by 2030, 1 in 6 people worldwide will be 60 or older. By 2050, that number will double to 2.1 billion, and those aged 80 or older will triple to 426 million. This demographic shift makes pharmacovigilance in older adults more essential than ever. Older adults are more prone to adverse drug reactions, drug interactions, and medication errors. Yet, they are often underrepresented in clinical trials and safety monitoring.

In this article, we explore the challenges of pharmacovigilance in older adults, highlighting the hidden risks faced by this vulnerable population.

The Aging Body and Changing Pharmacology in Older Adults

As we age, the body undergoes many changes that affect how it processes medications. Pharmacovigilance in older adults must account for these alterations: slower liver metabolism, declining kidney function, increased body fat, decreased muscle mass, and changes in gastrointestinal absorption.

Liver metabolism slows down, making it harder to break down drugs. Kidney function declines, reducing the body’s ability to eliminate waste and medications. At the same time, body fat increases while muscle mass decreases, altering how drugs are distributed throughout the body. Changes in gastrointestinal absorption also impact how medicines are taken up into the bloodstream. Together, these shifts make medication effects less predictable and increase the risk of adverse reactions in older adults.

These physiological changes are unpredictable and affect pharmacokinetics (how the body processes drugs) and pharmacodynamics (how drugs affect the body). A standard drug dose can become either ineffective or dangerously toxic in an elderly patient.

Increased Sensitivity to Medications

Older adults often experience more substantial drug effects, particularly with medications affecting the central nervous system, such as sedatives or antipsychotics. Pharmacovigilance in older adults must always consider the altered sensitivity of this vulnerable group.

Polypharmacy in Older Adults: A Double-Edged Sword

Polypharmacy – typically defined as the concurrent use of five or more medications – is a hallmark of geriatric care. It can be necessary to manage multiple chronic conditions, but it comes with serious risks.

Adverse drug reactions (ADRs) are becoming more common in older adults, especially those with multiple health conditions and on various medications. Around one in ten hospital admissions of older adults are related to ADRs, and about one in six older adults experience clinically significant ADRs during their hospital stay.

With every additional drug, the chances of experiencing ADRs increase. Certain drug combinations can also interact dangerously, either heightening toxicity or reducing a medication’s effectiveness. Managing complex medication schedules often becomes a challenge, leading to missed doses or mistakes. Over time, polypharmacy has been linked to serious consequences like falls, frailty, and cognitive decline.

Atypical Presentations of ADRs in Older Adults

In older adults, ADRs often don’t present with obvious symptoms. Instead, they may show up in subtle and easily overlooked ways, such as unexpected falls, confusion or delirium, dehydration, incontinence, or a sudden decline in overall functioning. These signs are frequently mistaken for normal aging or worsening of existing conditions, making it even more important to stay alert to the possibility of medication-related problems.

Underreporting of ADRs in the Elderly and the Role of Pharmacovigilance

Although elderly patients face a higher risk of ADRs, their cases are often underreported. Several factors contribute to this problem, including the tendency to attribute symptoms to normal aging, communication challenges like hearing loss or cognitive decline, and healthcare providers’ hesitation to report uncertain cases. A lack of proactive monitoring systems also plays a role. 

Pharmacovigilance in older adults must address these gaps by improving education, enhancing reporting systems, and fostering a culture of caution where it’s better to report a potential risk than to overlook it.

Conclusion

Pharmacovigilance in older adults is not a niche concern. It is a central pillar of safe healthcare in an aging world. It requires recognizing that older adults are not just “older versions” of younger patients but individuals with unique vulnerabilities.

By prioritizing pharmacovigilance in older adults, we can protect the golden years from being tarnished by preventable harm – ensuring that medicines heal, rather than hurt, those who have already given so much to society.

The path forward demands vigilance, compassion, innovation – and, above all, a commitment to see and serve older people with the respect and care they deserve.