E-Cigarette Directory Laws, Sales, and Product Availability From 3 Early-Adopting US States.

Importance: Flavored e-cigarettes are the most-used tobacco product among US youths and young adults. The US Food and Drug Administration (FDA) has authorized only 45 e-cigarette products, while thousands remain under review. Some states have enacted laws permitting sales of non-FDA-authorized products listed on state directories, but the impact of these laws is unknown. Objectives: To evaluate the association of directory laws with e-cigarette sales and product availability over time in Alabama, Oklahoma, and Louisiana, the first states to enact these laws. Design, Setting, and Participants: This cross-sectional study applied a synthetic difference-in-differences approach to assess state-level e-cigarette retail sales from the 4-week period ending January 31, 2021, through the 4-week period ending April 20, 2025. Alabama, Oklahoma, and Louisiana were compared with synthetic controls constructed from 31 states without directories, assessing changes before and after directory publication. Data were analyzed August 1, 2025, to July 20, 2026. Exposure: Implementation of directory laws. Main Outcomes and Measures: The primary outcome consisted of per capita e-cigarette nicotine sales, calculated as units sold × e-liquid volume × nicotine concentration, summed across products per state-month and divided by state population. Product availability was a secondary outcome, defined as the number of distinct products sold monthly in each state. Analyses were conducted overall and stratified by flavor and product type. Results: A total of 1904 state-month observations were included in the analysis. No associations of e-cigarette nicotine sales or product availability with directory listings were observed in Alabama or Oklahoma, where flavored disposables remained dominant. In Louisiana, the law was associated with a significant reduction in sales relative to synthetic controls (average treatment effect [ATT], -38.29% [95% CI, -53.10% to -18.80%). However, event-study analyses showed this decline was temporary, with the estimated treatment effect equal to -19.46% (95% CI, -27.32% to -10.76%) immediately after publication and reaching -63.43% (95% CI, -74.32% to -47.92%) in July 2024, 8 months after implementation. Sales then rebounded and the decrease became statistically nonsignificant by October 2024 as unlisted flavored disposables and menthol cartridges drove sales. In contrast, product availability in Louisiana declined persistently with an ATT of -53.55% (95% CI, -65.67% to -37.14%). In all states, more than half of sales were for unlisted products by the end of the study period. Conclusions and Relevance: In this cross-sectional study, directory laws in early-adopter states did not produce lasting declines in flavored e-cigarette sales. These findings suggest that directory laws instead might divert resources from evidence-based tobacco control strategies.