Frequent cannabis vaping, defined as vaping at least 10 times a month, more than doubled among high school seniors in the United States between 2018 and 2019, according to new research from NYU Grossman School of Medicine published online May 4 in the Journal of Adolescent Health. The rise in frequent use was even greater in certain subgroups such as students 18 years or older, female students, and those who reported using other drugs within the past year.