In a 4-week study, CBD-dominant cannabis flower was associated with lower anxiety, tension, and paranoia scores compared to THC-dominant cannabis, and THC did not increase anxiety, challenging the assumption that THC worsens anxiety.
People using cannabis for anxiety, mental health clinicians, cannabis dispensary counselors
CBD-dominant lowered anxiety more than THC-dominant
What the researchers found
All cannabis groups reported anxiety reduction over 4 weeks, but CBD-dominant use was associated with lower DASS anxiety scores (difference=-1.03, p=0.02) and lower acute tension and paranoia compared to THC-dominant. THC-dominant cannabis did not increase anxiety. All groups experienced positive mood and subjective drug effects.
Why it matters
This is one of the first studies examining legal market cannabis products with varying THC:CBD ratios in people with actual anxiety symptoms, providing ecologically valid data on what consumers might experience.
The numbers in context
42 non-users + 258 users. THC-dominant: 24% THC. Balanced: 12% THC + 12% CBD. CBD-dominant: <1% THC. CBD-dominant vs THC-dominant DASS anxiety: difference=-1.03 (p=0.02). POMS tension: difference=-0.41 (p<0.05). Paranoia: difference=-0.49 (p<0.05).
How the study worked
Quasi-experimental study with 42 non-cannabis-using participants with anxiety symptoms as controls and 258 cannabis users with anxiety randomly assigned to THC-dominant (24% THC), THC+CBD (12%/12%), or CBD-dominant (<1% THC) legal market flower for 4 weeks of ad libitum use.
What this study cannot tell us
Quasi-experimental, not fully randomized (non-users were a separate group). Self-selected participants. Ad libitum dosing means variable exposure. 4-week duration limits conclusions about long-term effects. Legal market products with variable consistency.
How to read the evidence
Quasi-experimental design with legal market products provides ecological validity but lacks blinding and full randomization.
When this study was published
2024 quasi-experimental study of legal market cannabis for anxiety (NCT03491384)
The bigger picture
The finding that THC did not worsen anxiety contradicts common clinical advice but aligns with many users' experience. The superior anxiety reduction with CBD-dominant products supports growing consumer interest in high-CBD, low-THC cannabis for anxiety management.
Questions still open
- Would these results replicate in a fully randomized, blinded trial? Is the CBD effect on anxiety sustainable long-term? What CBD:THC ratio optimizes anxiety reduction?
Common questions
Does THC make anxiety worse?
What type of cannabis is best for anxiety?
Read the original research
Acute and Extended Anxiolytic Effects of Cannabidiol in Cannabis Flower: A Quasi-Experimental ad libitum Use Study.
Cannabis and cannabinoid research, 9(4), 1015-1027
Citation
Bidwell, L Cinnamon; Martin-Willett, Renée; Skrzynski, Carillon; Lisano, Jonathon; Ortiz Torres, Marco; Giordano, Gregory; Hutchison, Kent E; Bryan, Angela D. (2024). Acute and Extended Anxiolytic Effects of Cannabidiol in Cannabis Flower: A Quasi-Experimental ad libitum Use Study.. Cannabis and cannabinoid research, 9(4), 1015-1027. https://doi.org/10.1089/can.2023.0187
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