Table 1.

Evidence Ratings for Therapeutic Benefits versus Harms of Cannabis

Diagnosis	Therapeutic Benefits	Refs.	Harms	Refs.	Future Research
SZ	There is minimal and equivocal evidence supporting a therapeutic role for cannabis, specifically CBD, in SZ.	[9, 76, 93, 101]	Cannabis use has been shown to have a strong correlation (dose- dependent) to poorer outcomes in and increased risk of psychosis.	[2, 33, 54, 100, 107, 113,116, 117,128, 145]	Further randomized, controlled trials are needed to determine CBD effects across heterogeneous populations of SZ. Additionally, further randomized, controlled studies looking at combined effects of CBD and THC are needed.
MDD	There is no clear evidence for a positive influence of cannabis in depression (only studies that show lack of association).	[34, 50] [111]	Evidence suggests more of a harmful influence of cannabis on the course of depression, specifically associated with adolescent onset of use.	[4, 5, 75, 106, 120, 129]	Longitudinal, prospective and controlled trials to investigate what preparation(s) of cannabis as well as what frequency and onset of use is associated with harms.
BD	There is no evidence of any therapeutic effect with cannabis use, besides acute relief shortly after use.	[121] [73, 126]	Cannabis use has been associated with harms, including increased risk of and outcomes in BD; however, there are equal findings with statistically insignificant associations.	[27, 86, 111, 144, 155]	Longitudinal, prospective and controlled trials to investigate what preparation(s) of cannabis as well as what frequency and onset of use is associated with harms.
PTSD	There is minimal evidence of any therapeutic effect with cannabis use. Benefits for have been reported mainly for sleep-related dysfunctions.	[18, 56, 78, 124]	There is minimal evidence of reported harms with cannabis use. Long-term effects of cannabis on PTSD are still unclear.	[45, 98, 141, 153]	Randomized, controlled trials with larger sample sizes are needed to understand potential therapeutic effects. Longitudinal, prospective trials are needed to understand potential harms.
GAD	There is no clear evidence for the therapeutic benefit of cannabis across anxiety disorders, despite self-reported claims.	[7, 19]	There is equivocal evidence suggesting either positive or lack of statistically significant associations between cannabis use and anxiety disorder or anxiety symptoms.	[27, 34, 37, 50, 66, 69, 130, 144]	Randomized, controlled trials and longitudinal, prospective studies are needed to associate specific preparations of cannabis with anxiety outcomes and risk for anxiety development.
Evidence Ratings
Rating 1: Minimal Evidence Case Reports & Retrospective Studies		Rating 2: Equivocal Evidence Case-Controls & Cross-Sectional Studies			Rating 3: Strong Evidence Randomized Controlled Trials

SZ, Schizophrenia; MDD, Major Depressive Disorder; BD, Bipolar Disorder, PTSD: Posttraumatic Stress Disorder; GAD, Generalized Anxiety Disorder.