Basel Weed Care: mid-point results show falling black-market demand

After 18 months of the pilot, 63 % of participants purchase exclusively through the regulated channel — the black-market share dropped from 41 % to 12 %.

The University Hospital Basel and the cantonal Department of Health released the mid-point results of the «Weed Care» study. 378 adult participants obtained lab-tested cannabis in nine participating pharmacies between January 2025 and July 2026.

Consumption volume remained stable (median 1.3 g/week) and risky combinations with alcohol dropped significantly (–34 %). No contamination incidents were reported. The results will be handed to the Swiss Federal Office of Public Health (FOPH) as input for the planned expansion to further cantons.