Large survey of Canadian medical cannabis patients reveals widespread substitution for prescription drugs, opioids, and alcohol

69.1% reported substituting cannabis for prescription drugs (35.3% of those for opioids), 44.5% for alcohol, 31.1% for tobacco, and 26.6% for illicit substances. Among the 610 mentions of specific opioid medications, patients reported total cessation in 59.3% of cases. Pain and mental health conditions accounted for 83.7% of respondents.

A 239-question cross-sectional survey of 2,032 Canadian medical cannabis patients registered with a federally authorized licensed producer (January 2017).

This is one of the largest and most detailed surveys of medical cannabis substitution patterns. The finding that nearly 60% of opioid substituters reported complete cessation adds significant individual-level data to the population-level evidence.

This study captures the behavior of patients in Canada's regulated medical cannabis program, providing a cleaner picture than studies of recreational users. The substitution patterns suggest cannabis is being actively used as an alternative to multiple substance categories.

Self-reported data without medical record verification. Patients registered with licensed producers may not represent all medical cannabis users. Cross-sectional design cannot establish causal substitution. Selection bias likely (patients who benefit from cannabis are more likely to respond).