Pharmacists Are Central to Closing the Medication Adherence Gap

Medication nonadherence continues to undermine the value of modern pharmacotherapy, with research and consensus reports showing that pharmacists, positioned at the intersection of prescribing and dispensing, are uniquely equipped to intervene. A 2025 report noted that for every 100 prescriptions written, only 50% to 70% are filled, 48% to 66% are picked up, and just 25% to 30% are ultimately taken as prescribed.¹

The Scope and Cost of Nonadherence

Nonadherence is not a marginal issue. A 2024 analysis published in Frontiers in Pharmacology, marking 2 decades since the seminal adherence report from the World Health Organization (WHO), found that nonadherence generates an estimated €80 billion to €125 billion in potentially avoidable direct and indirect costs annually in the European Union and was linked to nearly 200,000 deaths per year there.²

In the United States, the cumulative cost of nonadherence to prescription drugs reached approximately $529 billion in 2016, with per-patient costs ranging from $5271 to $52,341.² A separate paper in the Journal of Preventive Medicine and Hygiene cited data from the New England Healthcare Institute showing that 75% of Americans face difficulty taking medications as prescribed, with nonadherence linked to roughly 125,000 deaths annually in the United States.³

The clinical consequences extend across disease states. Nonadherence accounts for up to 48% of asthma deaths, an 80% increase in the risk of death from diabetes, and a 3.8-fold increase in the risk of death in the year following a heart attack.³ For cardiovascular disease (CVD) specifically, the CDC reports that patients adherent to antihypertensive medications were 30% to 45% more likely to achieve blood pressure control than those who were not and that nonadherence to CVD prevention medications is associated with significantly higher rates of premature death, hospitalization, and coronary revascularization procedures.⁴

Pharmacy-Based Interventions Show Cost-Effectiveness

The Community Preventive Services Task Force recommends tailored pharmacy-based interventions to support adherence to CVD prevention medications, finding them cost-effective for CVD prevention. These interventions typically begin with an assessment—using interviews or tools to identify a patient’s specific barriers—followed by tailored guidance and services such as focused medication counseling, motivational interviewing, pillboxes, medication cards, refill synchronization, and enhanced follow-up.⁴

Several structured strategies support this approach. Medication therapy management allows pharmacists to actively manage patients’ medications and identify, prevent, and resolve medication-related problems, while the appointment-based model gives patients a designated pickup day and shifts pharmacy staff toward proactively synchronizing refills rather than passively filling prescriptions on an unaligned schedule.⁴

Collaborative practice agreements formalize arrangements between prescribers and pharmacists that allow pharmacists to renew prescriptions, modify therapy according to protocol, and order lab tests. The CDC notes that the economic case is strong, showing that among patients with existing CVD, cost savings from averted health care use exceeded the cost of implementing these interventions, and higher adherence to medications for congestive heart failure, hypertension, and high low-density lipoprotein cholesterol reduced annual per-person health care spending by an estimated $7800, $3900, and $1250, respectively, compared with poorer adherence.⁴

From Compliance to Counseling-Based Adherence

Authors of the 2025 paper argued that pharmacists must transition “from an approach based on compliance to one founded on adherence,” emphasizing counseling as an ethically significant clinical service rather than a commercial add-on. They described pharmacy counseling as particularly valuable for patients facing comorbidity, polypharmacy, or prescriptions from multiple physicians—circumstances that easily generate confusion about medication regimens.³

They pointed to practical examples already underway in Italy, including a home care program at the Policlinico di Bari that uses patient-narrated disease histories to strengthen active pharmacovigilance and an oncology pharmacy program in the Emilia-Romagna region where pharmacists conduct scheduled interviews at each drug pickup to monitor adherence, evaluate drug interactions, and identify adverse effects.³

The same paper cautioned that expanding pharmacists’ counseling responsibilities raises ethical and medicolegal questions, including the risk of overstepping into physicians’ diagnostic domain, ensuring patient confidentiality in open pharmacy settings, and navigating potential conflicts of interest when products carry financial incentives. The authors called for standardized protocols defining the scope of pharmacist counseling and adequate compensation for the additional time such services require.³

A Call for Shared Responsibility

The Frontiers in Pharmacology consensus paper, developed by 10 international adherence experts using the WHO’s 5-dimension adherence framework, identified the whole-person care concept—built on collaboration among physicians, nurses, and pharmacists—as one of the top achievements in adherence management over the past 2 decades. Looking ahead, the experts proposed that medication adherence become a standard, nonjudgmentally documented measure in routine clinical practice and called for expanded reimbursement and insurance coverage for adherence-enhancing interventions.²

That sentiment was echoed by another publication, which reframed nonadherence as “a system-wide failure involving [health care providers], policymakers, and authorities” rather than a problem attributable to patients alone. They noted that a 20% improvement in CVD medication adherence correlates with an 8% reduction in cardiovascular events and a 12% decrease in mortality, and that trust in the broader health care system—reported at just 51% globally in a 2023 survey—shapes how much patients trust individual providers, including pharmacists.¹

REFERENCES

1. Pruitt SD, Khan R, Chaiyakunapruk N, et al. The silent epidemic of non-adherence – insights from the 2024 a:care congress. BMC Proc. 2025;19(suppl 10):13. doi:10.1186/s12919-025-00326-4

2. Kardas P, Bennett B, Borah B, et al. Medication non-adherence: reflecting on two decades since WHO adherence report and setting goals for the next twenty years. Front Pharmacol. 2024;15:1444012. doi:10.3389/fphar.2024.1444012

3. Ciliberti R, Bonsignore A. New integrations in patient care: the role of the pharmacist between couselling and medication adherence. J Prev Med Hyg. 2025;66(1):e38-e44. doi:10.15167/2421-4248/jpmh2025.66.1.3222

4. Pharmacy-based interventions to improve medication adherence. Centers for Disease Control and Prevention. May 15, 2024. Accessed June 30, 2026. https://www.cdc.gov/cardiovascular-resources/php/medication-adherence/index.html