PURPOSE: To document recent, national trends in vaping and use of flavored vaping solutions among US adolescents who use marijuana.

METHODS: Data come from Monitoring the Future, which conducted annual, cross-sectional, nationally-representative surveys from 2021 to 2024 of eighth, 10th, and 12th grade students.

RESULTS: Among adolescents who used marijuana in the past 12 months, the percentage who vaped it increased over the study period from 48% to 57% in eighth grade (p < .05), 60%-66% in 10th grade (p = .07), and 58%-67% in 12th grade (p < .01). The percentage of adolescents who used a flavored solution when vaping marijuana switched from a minority to a majority over the study period, from 47% to 63% (p < .01) in eighth grade, 41%-53% (p < .01) in 10th grade, and 36%-50% (p < .01) in 12th grade. The percentage of all adolescents who vaped a flavored marijuana solution in the past 12 months over the study period increased from 2% to 4% (p < .01) in eighth grade, 5%-6% in 10th grade (p = .25), and 7%-9% in 12th grade (p < .01).

DISCUSSION: The percentage of US adolescents who vaped flavored marijuana solutions increased from 2021 to 2024, one of very few drug outcomes that increased since the pandemic onset. With this increase, adolescents who used flavors to vape marijuana shifted from a minority to a majority and vaping became more common among adolescents who used marijuana. These results point to flavored marijuana vaping solutions as an increasingly important target for research and policy on adolescent marijuana use.