BACKGROUND-AIM:
The alarming global rise of synthetic nicotine use among youth is fueled by legislative loopholes^(1,2). Internationally, nicotine law definitions often focus on tobacco-derived nicotine, excluding synthetic nicotine products and leading to varying degrees of youth access to synthetic nicotine^(2,3). Cross-jurisdictional analysis on synthetic nicotine regulation is necessary to effectively close existing regulatory loopholes. This review investigates country-level variation in: (1) legislative definitions and (2) regulatory levers (i.e., access, taxation, labeling, promotions, and enforcement) to control synthetic nicotine products.

METHODS:
Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews guidelines, we included English-available legislation from^(3,4) Organization for Economic Co-operation and Development (OECD) countries and reviewed grey literature to contextualize national approaches^(4,5). Data were extracted using a predefined analytical framework. Study researchers participated in consensus meetings to ensure accurate data interpretation. Legal interpretations were validated through correspondence with regulatory authorities.

RESULTS:
Seven OECD countries were included: Australia, Canada, Ireland, Iceland, New Zealand, the United Kingdom (UK), and the United States (US). Among included countries, Australia and New Zealand have the strictest controls on synthetic nicotine. In Australia, synthetic nicotine access is restricted to a special access scheme⁶. In New Zealand, synthetic nicotine cannot be imported for sale or distribution; import is only allowed by prescription^(7,8). Iceland and the US both implemented amendments to existing tobacco legislation to regulate synthetic nicotine sale⁹⁻¹³. In contrast, Ireland, Canada and the UK have limited regulation of synthetic nicotine. In Ireland, nicotine pouches are not regulated by the Tobacco Products and Nicotine Products Act (2023), due to their synthetically derived form and are instead unregulated products available to youth^(14,15). In Canada, nicotine pouches are regulated as nicotine replacement therapy (NRT) under the Food and Drugs Act rather than the Tobacco and Vaping Products Act resulting in unrestricted access to pouches for youth¹⁶⁻¹⁸. Canadian Ministerial authorities have been emergently enacted through a supplementary order in 2024, temporarily prohibiting youth access; this emergency regulation is not recognized as ideal nor sustainable16-18. In the UK, NRT are regulated as medicines, but the definition of NRT excludes oral products (i.e. nicotine pouches), leaving these consumer products unregulated and available to youth^(19,20).

CONCLUSIONS:
Significant heterogeneity exists in synthetic nicotine legislation across OECD countries. As product innovation accelerates, regulatory frameworks are urgently needed to balance youth protection with equitable access to NRTs when clinically indicated.