By Darren Triller, PharmD

Which medication class leads to the highest number of emergency department visits for adverse drug events (ADEs) in the U.S.?

Many pharmacists would guess antibiotics. Antimicrobial resistance has been recognized as a global public health threat for years, and antimicrobial stewardship programs are now a standard component of healthcare delivery. Others would guess opioids, given decades of news coverage, policy initiatives, and public awareness campaigns addressing misuse and overdose.

Both are logical answers. Both are wrong.

The answer is antithrombotic medications, the anticoagulants and antiplatelet medications used by millions of Americans to prevent and treat conditions such as atrial fibrillation, venous thromboembolism, stroke, myocardial infarction, and peripheral arterial disease.

The scale of harm

Antithrombotics rank among the leading contributors to serious medication-related harm in the U.S. Among older adults, 5 of the 7 medications most commonly associated with emergency department visits for ADEs are anticoagulants or antiplatelet medications. Together, they account for more than 40% of ADE-related emergency department visits among Medicare beneficiaries, and half of those visits result in hospital admission.

The pharmacy profession has invested enormous effort in building systems to improve the safe and appropriate use of antibiotics. The profession has raised awareness of opioid-related harm and developed policies, education, and monitoring programs to address it. Pharmacists have also demonstrated considerable value to the healthcare system through improved patient outcomes and reduced overall health expenditures.

Yet, despite the magnitude of patient harm associated with antithrombotic therapy, many healthcare organizations still lack a systematic approach to ensuring these medications are used as safely and effectively as possible.

Bleeding is only one side of the equation

One reason may be that the challenges are less visible. Anticoagulants are commonly associated with bleeding, and bleeding is certainly important. But bleeding represents only one side of the equation.

Every day, patients experience preventable strokes, pulmonary emboli, deep vein thromboses, myocardial infarctions, and other thrombotic complications related to gaps in care, inappropriate therapy, poor adherence, inadequate monitoring, communication failures, and fragmented transitions between care settings. These events may not receive the same public attention as antibiotic resistance or opioid misuse, but their impact on patients, families, and healthcare systems is profound.

Managing antithrombotic therapy is among the most complex responsibilities in modern healthcare. The right drug, dose, duration, monitoring strategy, and transition plan can vary significantly between patients and clinical situations, and decisions frequently span multiple providers, care settings, and disciplines. 

That complexity creates both risk and opportunity.

Why pharmacy is positioned to lead

No single medical specialty owns antithrombotic management, which leaves pharmacy well-positioned to lead.

Pharmacists understand pharmacology, identify medication-related problems, educate patients, support transitions of care, and collaborate with physicians, nurses, administrators, and quality leaders. They also see the entire medication-use process in ways few other healthcare professionals can.

As healthcare focuses more on quality, safety, and value, antithrombotic stewardship clearly needs attention. The real question is why it hasn’t become a priority sooner.

A model borrowed from antimicrobial stewardship

Healthcare organizations around the world are beginning to apply the same systematic approaches that transformed antimicrobial stewardship to the use of anticoagulants and antiplatelet medications. The goal is straightforward. Reduce preventable thrombosis and bleeding while improving patient outcomes, healthcare quality, and resource utilization.

The Anticoagulation Forum offers a growing collection of antithrombotic stewardship resources, implementation tools, and educational materials designed to help organizations advance safer care. Recent publications have documented both the measurable impact of stewardship initiatives and practical approaches for securing executive leadership commitment to these programs.

This article is the first in a series exploring the evolving field of antithrombotic stewardship. Future installments will examine what antithrombotic stewardship is, why pharmacists are essential to its success, and how healthcare organizations can build sustainable programs that improve patient outcomes.

One of the greatest medication-safety opportunities in healthcare may be hiding in plain sight.

References

Anticoagulation Forum. (2026). Infographics and advocacy resources.

May, J. E., et al. (2024). Securing administrative leadership commitment for anticoagulation stewardship programs. Journal of the American College of Clinical Pharmacy.

Triller, D. M., et al. (n.d.). Advancing the delivery of antithrombotic therapy (ADAPT): A framework for improving quality and safety through antithrombotic stewardship programs. The Joint Commission Journal on Quality and Patient Safety.