Blood Test Trial Aims to Reduce Overprescription in Elderly

By the Editorial Team · Sunday, October 4, 2026

Researchers at the University of Southampton have launched a five-year trial in England to evaluate whether a blood test can guide GPs in choosing safer medications for elderly patients taking multiple prescriptions. If successful, this approach could personalize drug treatments, reduce adverse side effects, and lower NHS costs related to overprescribing in the aging population.

A new trial in England aims to determine whether a simple blood test can help general practitioners (GPs) identify the safest and most effective medications for elderly patients on multiple prescriptions. The five-year, £3 million study is being led by researchers at the University of Southampton in collaboration with the National Institute for Health and Care Research (NIHR).

The study will focus on individuals aged 65 and older who are taking five or more medications daily—a group that includes nearly eight million people in England. Of these, more than two million take ten or more medicines concurrently. Researchers highlight that over 90 percent of people have genetic variations that can alter how they respond to certain drugs, potentially either reducing effectiveness or increasing the risk of adverse reactions.

Currently, overprescription is believed to cost the National Health Service (NHS) more than £2 billion annually. Additionally, two-thirds of hospital admissions among patients over 65 are linked to preventable side effects from medications. Addressing these issues, the trial will use genetic testing as part of medication reviews in routine primary care settings.

The trial will enroll over 1,000 patients across 30 GP practices in England. Participants will be divided into two groups: one receiving standard medication reviews and the other undergoing reviews guided by the results of their genetic tests. The blood test under development aims to identify genetic markers that influence how patients metabolize commonly prescribed drugs for older adults.

Dr. Kinda Ibrahim, associate professor at the University of Southampton and a trained pharmacist, explained the rationale behind the study. “We have millions of people already taking high volumes of medications. We don’t know if the medications work for them,” she said. Ibrahim emphasized the potential for genetic testing to improve treatment responses and reduce hospital admissions, but noted that definitive evidence requires completion of the trial.

In addition to the trial, NHS guidelines recommend that individuals over 65 who are considered frail and are prescribed ten or more medications be invited for annual medication reviews. To support the growing needs of an aging population, training an additional 1,850 geriatricians by 2030 is planned, aiming to provide one specialist for every 500 people aged 85 and above.

The outcomes of this trial could influence future prescribing practices, potentially offering a more personalized approach to medication management for elderly patients and reducing the risks associated with polypharmacy.

This article was reported by synthesizing coverage from multiple independent news outlets to present a balanced, unbiased account. Read about our editorial standards. Spotted an error? Let us know.