Social Norm Nudging Boosts Initial Medication Adherence, Study Finds

Medication adherence, or the extent to which patients take medications as prescribed, is a strong predictor of improved clinical outcomes and lower health care costs. Nonadherence of any kind—forgetting doses, stopping due to adverse effects, or simply choosing not to take a medication—costs the average patient between $5000 and $50,000 annually.¹

At diagnosis, patients’ willingness to take their medications is a critical factor when assessing the likelihood of long-term adherence.² Other factors include past refill habits, health care usage, and health history. Furthermore, patients take their medication regimens more seriously after medical events or if they already take other medications.

However, patients are less likely to maintain adherence for so-called “silent conditions” because medications do not improve symptoms or provide immediate benefit. Instead, they help prevent medical emergencies resulting from longstanding untreated conditions such as hypertension, hyperlipidemia, or diabetes. For example, patients cannot feel consistently high blood glucose levels, but, over time, this leads to secondary manifestations such as diabetic foot infections or neuropathy.

A team of Japanese community pharmacists used social norm nudging and numerical adverse effect information during counseling to evaluate their impact on initial medication adherence. Social norm nudging frames medication use as a common and accepted part of the patient’s disease management. They examined 54 patients with newly diagnosed diabetes, hypertension, or hyperlipidemia.³

Receiving a new diagnosis can be daunting, but in the first intervention, pharmacists aimed to improve initial adherence by normalizing the medication and fostering a sense of commonality. For example, the statement, “Many people take this medication and live happy and healthy lives” puts patients at ease, because they know their lives will not be affected with proper medication adherence.

When introduced to a new medication, it is natural for patients to ask about potential adverse effects. However, lengthy discussions of every possible adverse effect may unintentionally convince patients that these events are common. However, numerical adverse effect information failed to significantly improve patients' willingness to initiate therapy. In the second intervention, pharmacists aimed to reduce patient tendencies to overestimate adverse effect prevalence. For example, a pharmacist may tell a patient, “There is less than a 1% chance of developing an anaphylactic reaction” when addressing concerns about a medication’s safety profile.³ 

The team compared the 2 interventions simultaneously to determine which produced greater improvements in initial adherence. They gave patients pre-randomized baseline questionnaires that gauged their characteristics and subjective numeracy, meaning their ability to understand mathematical concepts like percentages. After the assessment, participants received both interventions, 1 intervention, or no interventions. Pharmacists assessed medication willingness before and after the intervention using a 7-point scale.³

The results demonstrated that social norm nudging significantly increased patients’ initial willingness to take medication. Regardless of numeracy level, numerical adverse effect information failed to significantly improve adherence rates.³

Medication adherence remains one of the most fixable levers in chronic disease management, yet it hinges on subtle psychological factors that pharmacists are uniquely positioned to address during counseling. This study’s findings suggest that simple, low-cost communication strategies can meaningfully shift patients’ willingness to start therapy, even for the silent conditions that lack immediate symptomatic feedback.

Notably, the failure of numerical adverse effect information to move the needle suggests that patients’ adherence concerns may be driven less by statistical risk assessment and more by a need for reassurance and belonging. As pharmacists continue to serve as a frontline touchpoint for newly diagnosed patients, incorporating social norm nudging into routine counseling could offer a practical, scalable way to improve long-term adherence and, ultimately, reduce the downstream costs and complications of untreated chronic disease.

REFERENCES

1. Cutler RL, Fernandez-Llimos F, Frommer M, Benrimoj C, Garcia-Cardenas V. Economic impact of medication non-adherence by disease groups: a systematic review. BMJ Open. 2018;8(1):e016982. doi:10.1136/bmjopen-2017-016982

2. Lauffenburger JC, Franklin JM, Krumme AA, et al. Predicting adherence to chronic disease medications in patients with long-term initial medication fills using indicators of clinical events and health behaviors. J Manag Care Spec Pharm. 2018;24(5):469-477. doi:10.18553/jmcp.2018.24.5.469

3. Yoshida A, Kitamura S, Nakai M, Horii N, Ohshima S, Oshima S. Pharmacist-led communication strategies using social norm nudging and numerical information: a randomized field study on the willingness of Japanese patients to initiate treatment. Int J Pharm Pract. 2026;riag088. doi:10.1093/ijpp/riag088