Among 3,164 patients in France's medical cannabis program, 3% experienced serious adverse reactions — mainly neurological, GI, and psychiatric — with 6 acute coronary events and 8 suicidal thoughts but no psychosis and only 1 case of misuse.
Medical cannabis regulators, prescribing physicians, patients considering medical cannabis, and health policy researchers
What the researchers found
37.5% of patients reported at least one ADR; 3% had serious ADRs; most common: neurological (37.2%), GI (16.9%), psychiatric (15.2%); 6 acute coronary syndromes; 8 suicidal thoughts (half without prior psychiatric history); 1 misuse case; 0 psychosis.
Why it matters
France's cautious, government-monitored approach to medical cannabis provides the most rigorous safety data from a national program — the 3% serious event rate and absence of psychosis are reassuring.
The numbers in context
3,164 patients; 37.5% ≥1 ADR; 3% serious; 6 acute coronary syndromes; 8 suicidal thoughts (4 without prior psychiatric history); 1 suicide attempt; 7 withdrawal syndromes; 1 misuse; 0 psychosis cases.
How the study worked
Observational safety analysis of the French national medical cannabis experimentation registry (RECANN) plus pharmacovigilance/addictovigilance databases from March 2021 to March 2024, covering 3,164 patients.
What this study cannot tell us
Observational without comparator group; under-reporting likely in registry systems; 3-year timeframe may miss long-term effects; French patient selection criteria may differ from other programs.
How to read the evidence
Large national registry with systematic pharmacovigilance monitoring, but observational without control group and subject to reporting bias.
When this study was published
Published in 2026 covering 2021-2024, providing 3 years of safety data from a carefully controlled national program.
The bigger picture
The absence of psychosis cases in 3,000+ patients under medical supervision contrasts sharply with recreational use concerns — suggesting that controlled medical use has a meaningfully different risk profile.
Questions still open
- Would the safety profile differ with longer follow-up? Should the coronary syndrome cases prompt cardiac screening for medical cannabis patients?
Common questions
How safe is medical cannabis in France's program?
What are the most common side effects of medical cannabis?
Read the original research
Medical Cannabis Use in France: An Observational Safety Study Based on the RECANN Registry and the Pharmacovigilance/Addictovigilance System From 2021 to 2024.
Fundamental & clinical pharmacology, 40(2), e70074
Citation
Chevallier, Cécile; Batisse, Anne; Monzon, Emilie; Richard, Nathalie; Authier, Nicolas; Chenaf, Chouki; Gaboriau, Louise; Ferey, Véronique; Chretien, Basile; Fedrizzi, Sophie; Auffret, Marine. (2026). Medical Cannabis Use in France: An Observational Safety Study Based on the RECANN Registry and the Pharmacovigilance/Addictovigilance System From 2021 to 2024.. Fundamental & clinical pharmacology, 40(2), e70074. https://doi.org/10.1111/fcp.70074
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