New Research Reveals the Prevalence of Drug-Drug Interactions and the Economic Impact on the Healthcare System

Studies show an alarming prevalence of concurrent ingestion of interacting substances by patients and that providing physicians with clear, objective information leads to a reduction of interactions and costs for patients

NASHVILLE, TN (November 5, 2018) – Aegis Sciences Corporation, a leading healthcare company that provides clinically innovative testing and consulting services to providers, recently funded and published two scientific studies to identify the prevalence of drug-drug interactions (DDIs) and measure the economic impact they have on patients and the healthcare system. The analyses for both studies were conducted using the results of the InterACT Rx™ test, which include objective and definitive identification of substances known to interact with DDI-prone medications commonly prescribed in the treatment of chronic pain and behavioral health disorders.

“Objectively knowing which medications their patients are taking can make a world of difference for physicians as they prescribe different therapies,” said Elaine Jeter, M.D., medical director for Aegis. “At a macro level, it leads to reduced costs for patients and the overall healthcare system, and if you narrow it down, it could be life-saving information as doctors can avoid the adverse effects of dangerous drug-drug interactions.”

Published in the journal Expert Opinion on Drug Metabolism & Toxicology, the first study, “Characterization of Drug-Drug Interactions in Patients Whose Substance Intake Was Objectively Identified by Detection in Urine,” found that one in three patients that underwent InterACT Rx™ testing had at least one drug interaction objectively identified between two recently ingested substances. Of note, around 11% of these interactions were identified as severe or contraindicated. These kinds of interactions have been shown to contribute to patient harm, hospitalization and increased healthcare costs.

A second study, “Impact of Definitive Drug–Drug Interaction Testing on Medication Management and Patient Care,” published in the journal Drugs – Real World Outcomes, demonstrated a reduction in all-cause and pain-related outpatient visits as well as medication use when comparing patient medical records prior to and after a drug interaction was identified via InterACT Rx™ testing.

“Our findings in patients meeting polypharmacy criteria were particularly eye opening, as we saw a significant change in the prevalence of severe and contraindicated DDIs identified in those individuals that had recently ingested five or more substances,” said Joshua Schrecker, Pharm. D, a member of the Aegis clinical team. “This was particularly true in younger patients, potentially indicating providers may tend to overlook appropriate management of DDIs within this age group.”

In the first study, researchers looked at over 15,000 patients and found that nearly one in five met polypharmacy criteria (detection of greater than or equal to 5 substances). Polypharmacy patients were four times more likely to have a DDI identified and five times more likely to have a severe or contraindicated interaction identified. This was particularly true in patients 18-44 years old contrary to the belief that elderly patients are most prone to being prescribed interacting medications.

The second study took a retrospective look at 262 patients with chronic pain and/or behavioral health disorders being treated at two facilities and analyzed pre- and post-index date outcomes, including DDI test results, frequency of outpatient visits, and changes in prescribing behaviors. Researchers found that once DDIs were identified via InterACT Rx™ testing, patients had significantly less all-cause outpatient visits per month, reducing costs by 22% per patient. Cost savings were also shown for pain-related outpatient visits with the average cost declining by 23% per month. Additionally, prescriptions for opioids decreased by 12.7% in the post-index period in comparison to prescriptions written prior to completion of InterACT Rx™ testing.

In this study, patients were tested using Aegis’ InterACT Rx™ test to identify drug interactions with commonly prescribed medications in the treatment of chronic pain and behavioral health disorders. The test identifies recently ingested substances capable of causing DDIs and provides physicians with clinically actionable reports.

“We found that by using InterACT Rx™, physicians could enhance their current DDI practices and reduce the frequency and severity of DDIs,” said Cheryl Hild, Ph.D., vice president of quality at Aegis. “As we look at the results from both of these studies, it is clear that drug interactions are affecting a large number of patients, and by testing for and identifying these interactions, clinicians can improve medication management and overall health outcomes for patients while reducing overall health system costs.”

InterACT Rx™ is a definitive test that detects over 120 substances known to cause drug-drug interactions (DDIs), including non-prescription medications and herbal treatments. InterACT Rx™ is designed to reduce the risk of adverse drug events (ADEs) associated with DDIs through objective identification and reporting of interactions. For more information about InterACT Rx™, visit

About Aegis Sciences Corporation

Founded in 1990, Aegis Sciences Corporation is a laboratory sciences company based in Nashville, Tenn., that provides science-driven testing and consulting services for clients such as healthcare providers, pharmaceutical companies, professional and amateur sports organizations, leading college and university athletic programs, Fortune 500 corporations, and government agencies throughout the United States. For more information please visit


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