FDA authorisation of Zyn nicotine pouches: cross-sectional analysis of public discourse on X

BACKGROUND: On 16 January 2025, the U.S. Food and Drug Administration (FDA) authorised marketing of 20 Zyn oral nicotine pouch products, the first US authorisation of this category. Public interpretation may shape perceptions of safety and nicotine use. This study examined discourse on X following authorisation. METHODS: Posts containing 'Zyn' or '#Zyn' were extracted from X from 16-23 January 2025. After excluding reposts, quote posts, non-English posts and unrelated content, 549 posts were analysed. Using an inductive approach, four coders classified posts into 10 themes and coded sentiment as supportive, opposed or neutral. Negative binomial regression models estimated associations between themes and engagement, reported as incidence rate ratios (IRRs) for views, likes, replies, reposts and quotes. RESULTS: Most posts were neutral (58.1%), followed by supportive (28.6%) and opposed (13.3%). The most prevalent themes were news (68.7%) and public health benefits (41.0%), followed by government distrust (16.0%) and potential harms (11.1%). Supportive posts emphasised harm reduction, whereas opposed posts highlighted regulatory distrust and concerns about addiction and youth uptake. Flavour discussion (9.5%) was strongly associated with higher engagement across metrics (all p<0.01). Posts addressing potential harms or policy inconsistencies generated lower engagement on selected metrics. CONCLUSION: Discourse was dominated by informational sharing and harm reduction framing, alongside regulatory scepticism. The strong association between flavour discussion and engagement indicates that flavour-related content was highly visible in the immediate X discourse surrounding the FDA authorisation. Clear communication about FDA marketing authorisation is needed to prevent misinterpretation as endorsement of safety.