Medical Cannabis in the United States: Comparing 2017 and 2024 State Qualifying Conditions to the 2017 National Academies of Sciences Report

Abstract

Objective

To compare the 2017 National Academies of Sciences, Engineering, and Medicine cannabis report to state medical cannabis (MC) laws defining approved qualifying conditions (QC) from 2017 and 2024 and to determine the evidence level of the QCs approved in each state.

Patients and Methods

The 2017 National Academies of Sciences (NAS) report assessed therapeutic evidence for over 20 medical conditions treated with MC. We identified the QCs of 38 states (including Washington DC) where MC was legal in 2024 and compared them to the QCs listed by these states in 2017. The QCs were then categorized on the basis of NAS-established levels of evidence: limited, moderate, or substantial/conclusive evidence of effectiveness, limited evidence of ineffectiveness, or no/insufficient evidence to support or refute effectiveness. This study was completed from January 31, 2023 to June 20, 2024.

Results

Most states listed at least one QC with substantial evidence—80.0% in 2017 and 97.0% in 2024. However, in 2024 only 8.3% of the QCs on states’ QC lists met the standard of substantial/conclusive evidence. Of the 20 most popular QCs in the country in 2017 and 2024, one only (long-term pain) was categorized by the NAS as having substantial evidence for effectiveness. However, 7 were rated as either ineffective (eg, glaucoma) or insufficient evidence.

Conclusion

Most QCs lack evidence for use on the basis of the 2017 NAS report. Many states recommend QCs with little evidence (amyotrophic lateral sclerosis) or even those for which MC is ineffective (depression). These findings highlight a disparity between state-level MC recommendations and the evidence to support them.