Characteristics of cannabis warnings in the United States: A content analysis

Objectives: The goal of this study was to describe characteristics of warnings from state cannabis programs in the United States. Methods: From September 2024 to February 2025, we compiled regulations related to cannabis warnings on product packages in states with legalized cannabis sales (medical and adult-use), verifying regulations with regulators from each state. Two coders independently coded warning regulations for different characteristics. Results: We identified 60 state cannabis programs across the United States with legalized cannabis sales, of which 56 (93%) required cannabis warnings. Of the programs requiring warnings, 55% included warning content about a specific health risk, most often addiction (41%). Few programs had warnings about cannabis' effects on mental health (16%), respiratory health (5%), or cardiovascular health (4%). Few programs required warnings to contrast with backgrounds (23%), rotating warnings (7%), or front-of-package warnings (4%). The mean number of words in warnings was 57 (Standard Deviation: 30), and the mean reading level was 9th grade. Conclusions: Although 93% of cannabis programs with legalized sales require warnings, only half mention specific health risks; less than 10% require rotating or front-of-package warnings; and warnings may be difficult to read and understand. Further research is vital to strengthen cannabis warning labels.