IMPORTANCE The market sector of flavored commercial nicotine products without tobacco leaves recently expanded to nicotine pouches. Comprehensive epidemiologic analyses of patterns and trends in youth use of commercial nontobacco nicotine products are lacking.

OBJECTIVE To estimate US youth nicotine pouch and e-cigarette use prevalence and associated sociodemographic variables in 2023 and 2024.

DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study used data from annual surveys conducted in school with a nationally representative sample of 10th and 12th graders in 2023 and 2024 as part of the Monitoring the Future Study.

EXPOSURES Self-reported sex, race, ethnicity, and college plans; survey year; grade; and population density.

MAIN OUTCOMES AND MEASURES The primary outcomes were lifetime, past-12-month, and past-30-day self-reported nicotine pouch (yes or no) and e-cigarette (yes or no) use and co-use patterns (exclusive pouch without e-cigarettes, exclusive e-cigarette without pouches, or dual use).

RESULTS Of the 10 146 study participants (4886 [48.2%] male and 4818 [47.3%] female; 5674 [51.6%] in 10th grade and 4472 [48.4%] in 12th grade), nicotine pouch use increased from 2023 vs 2024 for lifetime use (3.0% [95% CI, 2.3%-4.0%] vs 5.4% [95% CI, 4.2%-6.8%]; risk difference [RD], 2.3% [95% CI, 1.0%-3.6%]; risk ratio [RR], 1.76 [95% CI, 1.30-2.40]), use in the past 12 months (2.4% [95% CI, 1.7%-3.2%] vs 4.6% [95% CI, 3.5%-5.9%]; RD, 2.2% [95% CI, 1.0%-3.4%]; RR, 1.95 [95% CI, 1.39-2.74]), and use in the past 30 days (1.3% [95% CI, 0.8%-1.8%] vs 2.6% [95% CI, 1.9%-3.4%]; RD, 1.3% [95% CI, 0.5%-2.1%]; RR, 2.05 [95% CI, 1.33-3.16]). E-cigarette use did not significantly change from 2023 to 2024 for lifetime use (28.5% [95% CI, 26.3%-30.7%] vs 26.7% [95% CI, 24.3%-29.3%]) and past-30-day use (13.4% [95% CI, 11.8%-15.2%] vs 11.8% [95% CI, 10.2%-13.7%]) but decreased for past-12-month use (20.0% [95% CI, 18.1%-22.0%] vs 17.6% [95% CI, 15.7%-19.7%]). From 2023 to 2024, exclusive nicotine pouch and pouch plus e-cigarette dual use generally increased, whereas exclusive e-cigarette use decreased, collectively constituting no significant change in the prevalence of any nontobacco nicotine use (using 1 or both products) across years. Demographic comparisons collapsed across 2023 to 2024 found that (1) male individuals reported higher nicotine pouch use prevalence than female individuals, whereas female individuals reported higher e-cigarette use prevalence than male individuals; (2) rural vs urban and non-Hispanic White vs Hispanic youths were more likely to use each product, with larger differences for pouches than e-cigarettes; and (3) nicotine pouch and e-cigarette use prevalence was higher among 12th vs 10th graders and those without vs with 4-year college plans.

CONCLUSIONS AND RELEVANCE In this cross-sectional study, commercial nontobacco nicotine use in US 10th and 12th graders shifted from 2023 to 2024, marked by a doubling in nicotine pouch past-30-day use, an increase in pouch plus e-cigarette dual use, and a decrease in exclusive e-cigarette use. Prioritizing surveillance, regulation, and prevention addressing pediatric nicotine pouch use warrants consideration.