Table 1_Frequency, causes, and duration of drug shortages in South Korea, 2018–2024: a nationwide descriptive analysis of regulatory reporting data and temporal patterns across the COVID-19 pandemic.docx

Analyses were descriptive; no causal inference was intended.</p>Results<p>A directly substitutable product with the same active ingredient, strength, and dosage form was available for only 269 of 868 drugs (31.0%). Cause structures differed by event type: internal supply issues predominated among temporary supply disruptions (183/396 cause attributions, 46.2%) and business decisions among permanent discontinuations (418/720, 58.1%).

Among temporary supply disruptions, regulatory constraints showed the longest durations (median 104 days; IQR 63.3–328) and the largest share lasting ≥366 days (25.0%). Products with ≥2 reported drug shortages were more frequent among orphan drugs (23.3%) and withdrawal-prevention drugs (21.1%), whereas Korean essential drugs showed a widely dispersed duration distribution (median 48 days; IQR 29.8–233.8; 25.6% > 180 days).

The numbers of temporary supply disruptions were 53, 106, and 178 in the pre-COVID-19, COVID-19, and later COVID-19/recovery periods, respectively. While internal supply issues remained the leading reported cause throughout (69.8%, 53.4%, and 39.5%), the relative contribution of raw-material supply disruptions (11.3%–26.7%) and increased demand (9.4%–23.1%) grew.</p>Conclusion<p>The patterns observed are consistent with structural vulnerabilities related to market incentives, regulatory processes, and API import dependence, with raw-material and demand-related causes becoming more prominent in the later study periods.

Potential policy responses, each requiring separate evaluation, include supply diversification, domestic API production, cost-compensation for economically vulnerable essential medicines, and a risk-based early-warning system with severity-tiered responses.</p>