Prescription volume and costs of over-the-counter–like drugs in Japan by patient and healthcare facility characteristics: A nationwide descriptive study

Abstract Introduction “Over-the-counter (OTC)-like drugs” are prescription medicines that contain the same or similar active ingredients as OTC drugs but receive reimbursement under Japan’s universal health insurance system. Despite ongoing policy discussions regarding the potential exclusion of these drugs from insurance coverage or increased patient cost-sharing, evidence describing their real-world prescription volume and costs is limited. We aimed to characterize the use of representative OTC-like drugs in Japan and examine variations by patient and healthcare facility characteristics. Methods This nationwide descriptive study was conducted using two claims-based data sources. From the National Database of Health Insurance Claims Open Data, we summarized the overall annual prescription volume and costs, further stratified by sex and age group, for fiscal years (FYs) 2018–2023. Using the DeSC database, we performed additional stratified analyses by comorbidity burden, health insurance type, and healthcare facility type. Five OTC-like drug categories were examined: oral single-agent acetaminophen, oral single-agent nonsteroidal anti-inflammatory drugs, topical anti-inflammatory patches, second-generation antihistamines, and heparinoid-containing topical preparations. Results In FY2023, the five OTC-like drug categories accounted for 17.4 billion prescriptions nationwide (139.6 per capita) and total costs of 288.1 billion yen (2317.0 yen per capita). Heparinoid-containing topical preparations and topical anti-inflammatory patches comprised the largest prescription volumes, whereas second-generation antihistamines and topical anti-inflammatory patches accounted for the highest costs. Prescription volume and costs were higher among females and increased markedly with age, particularly for topical anti-inflammatory patches. Per capita values also increased with greater comorbidity burden, being the highest among individuals covered by the Medical Care System for the Advanced Elderly. Clinics showed higher per capita prescription volume and costs than hospitals. Conclusions The use of representative OTC-like drugs in Japan is large and varies considerably by patient and healthcare facility characteristics. These findings provide important evidence to inform future policy discussions on OTC-like drugs.