Young Adult Cannabis Use Kept Rising Through COVID in Washington State

Cannabis use among young adults in Washington State continued its pre-pandemic upward trend through 2021, while alcohol, cigarette, and e-cigarette use declined.

Fleming, Charles B et al.·AJPM focus·2025·Moderate EvidenceLongitudinal Cohort
RTHC-06467Longitudinal CohortModerate Evidence2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Longitudinal Cohort
Evidence
Moderate Evidence
Sample
N=12,516

What This Study Found

Past-month cannabis use among 18-25 year olds increased by 1.6 percentage points per year from 2016-2019, with no pandemic-related disruption. Meanwhile, alcohol, cigarette, and e-cigarette use all declined.

Key Numbers

Cannabis: +1.6 pp/year (95% CI 0.6-2.6), no pandemic deflection. Cigarettes: -3.8 pp deflection. E-cigarettes: -2.9 pp deflection in 2020. Under-21 cannabis: -7.5 pp deflection in 2020. N=12,516.

How They Did This

Population-based survey of 12,516 young adults aged 18-25 across 6 annual waves (2016-2021) of the Washington State Young Adult Health Survey.

Why This Research Matters

Washington legalized recreational cannabis in 2012, making this a mature legal market. Cannabis use trends were resilient to pandemic disruption while other substance use declined.

The Bigger Picture

The diverging trends suggest cannabis has established a different user base and supply chain in legal states, one less disrupted by pandemic-related social changes.

What This Study Doesn't Tell Us

Single state with established legal market. Survey-based self-report. Cannot isolate pandemic effects from other policy changes.

Questions This Raises

  • ?Why did under-21 cannabis use dip in 2020 while legal-age use didn't?
  • ?How much of the e-cigarette decline was pandemic vs policy-driven?

Trust & Context

Key Stat:
Cannabis use rose 1.6 percentage points per year with no pandemic disruption
Evidence Grade:
Large population-based survey across 6 years, though limited to one state.
Study Age:
2025 study
Original Title:
Young Adult Cannabis, Alcohol, Nicotine, and Nonprescribed Pain Reliever Use in Washington State Before and During COVID-19 Pandemic.
Published In:
AJPM focus, 4(4), 100342 (2025)
Database ID:
RTHC-06467

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Follows a group of people over time to track how outcomes develop.

What do these levels mean? →

Frequently Asked Questions

Did the pandemic change cannabis use among young adults?

Not significantly. Cannabis use continued its pre-pandemic upward trend. The only exception was a temporary dip among under-21 users in 2020.

Why did e-cigarette use decline during the pandemic?

The decline likely reflects both pandemic disruption and Washington State's 2020 restrictions on flavored vaping products.

Read More on RethinkTHC

Cite This Study

RTHC-06467·https://rethinkthc.com/research/RTHC-06467

APA

Fleming, Charles B; Martinez, Griselda; Rhew, Isaac C; Kilmer, Jason R; Larimer, Mary E; Guttmannova, Katarina. (2025). Young Adult Cannabis, Alcohol, Nicotine, and Nonprescribed Pain Reliever Use in Washington State Before and During COVID-19 Pandemic.. AJPM focus, 4(4), 100342. https://doi.org/10.1016/j.focus.2025.100342

MLA

Fleming, Charles B, et al. "Young Adult Cannabis, Alcohol, Nicotine, and Nonprescribed Pain Reliever Use in Washington State Before and During COVID-19 Pandemic.." AJPM focus, 2025. https://doi.org/10.1016/j.focus.2025.100342

RethinkTHC

RethinkTHC Research Database. "Young Adult Cannabis, Alcohol, Nicotine, and Nonprescribed P..." RTHC-06467. Retrieved from https://rethinkthc.com/research/fleming-2025-young-adult-cannabis-alcohol

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.