Medical Cannabis Did Not Improve ADHD Symptoms in People With Chronic Pain | Research

The takeaway

In a 12-month study of adults with chronic pain, medical cannabis use was not associated with changes in ADHD symptoms overall, though high-THC products showed a small benefit in those with minimal baseline ADHD symptoms.

People considering cannabis for ADHD, clinicians fielding patient questions about cannabis and attention, and ADHD researchers.

What the researchers found

Medical cannabis use was not associated with changes in ADHD symptoms in the full sample or among those with moderate/severe baseline ADHD symptoms. Among the subgroup with minor/no baseline ADHD symptoms, high-THC medical cannabis was associated with a small decrease in ADHD symptoms compared to low-THC products.

Why it matters

Social media and patient anecdotes have driven interest in cannabis as an ADHD treatment. This study provides longitudinal evidence that cannabis does not improve ADHD symptoms in people who actually have them, countering a popular but unsupported narrative.

The numbers in context

N=223. 12-month follow-up with quarterly assessments. No significant association between MC use and ADHD symptom change in full sample or moderate/severe ADHD subgroup. Small decrease in ADHD symptoms with high-THC (vs. low-THC) MC only in those with minor/no baseline symptoms.

How the study worked

Longitudinal cohort study of 223 adults with chronic pain followed for 12 months with quarterly assessments. Mixed-effects linear regression tested associations between medical cannabis use (and THC level) and change in ADHD symptoms, stratified by baseline ADHD severity and pain catastrophizing.

What this study cannot tell us

All participants had chronic pain, limiting generalizability to ADHD populations without pain. Small sample size reduces power to detect modest effects. Observational design cannot rule out confounders. Cannabis products and doses were not standardized.

How to read the evidence

Longitudinal design with repeated measures is a strength, but small sample, chronic pain comorbidity, and observational design limit the conclusions.

When this study was published

Published 2025.

The bigger picture

The null finding for people with actual ADHD symptoms is important because it contradicts widespread anecdotal claims. The small positive finding in people without ADHD symptoms may reflect general effects of THC on attention or focus rather than a specific ADHD benefit.

Questions still open

Whether the small benefit in mild-symptom participants reflects genuine cognitive effects of THC or statistical noise
How these findings would change in a sample of people with diagnosed ADHD but no chronic pain

Common questions

Does this prove cannabis does not help ADHD?

It does not prove it definitively, but it adds to a pattern of null findings. The study found no benefit for people with actual ADHD symptoms, which is consistent with the limited clinical evidence available.

Why do some people with ADHD feel cannabis helps them?

Cannabis can reduce anxiety and increase present-moment focus, which some people interpret as ADHD improvement. However, these subjective effects may not translate into measurable changes on validated ADHD symptom scales, and chronic use may worsen executive function over time.

Read the original research

ADHD Symptoms and Medical Cannabis Use Among Adults With Chronic Pain.

Journal of attention disorders, 29(9), 757-765

View on PubMed ↗Publisher’s paper ↗

Citation

Saunders, David; Slawek, Deepika; Zhang, Chenshu; Sohler, Nancy; Cunningham, Chinazo; Minami, Haruka; Starrels, Joanna; Arnsten, Julia; Levin, Frances. (2025). ADHD Symptoms and Medical Cannabis Use Among Adults With Chronic Pain.. Journal of attention disorders, 29(9), 757-765. https://doi.org/10.1177/10870547251336841