Most trials showed improvement in symptoms associated with cannabinoids but these associations did not reach statistical significance in all trials .
There was an increased risk of short-term AEs with cannabinoids , including serious AEs .
Common AEs included dizziness , dry mouth , nausea , fatigue , somnolence , euphoria , vomiting , disorientation , drowsiness , confusion , loss of balance , and hallucination .
CONCLUSIONS AND RELEVANCE There was moderate- quality evidence to support the use of cannabinoids for the treatment of chronic pain and spasticity .
There was low- quality evidence suggesting that cannabinoids were associated with improvements in nausea and vomiting due to chemotherapy , weight gain in HIV infection , sleep disorders , and Tourette syndrome .
Cannabinoids were associated with an increased risk of short-term AEs
IMPORTANCE Cannabis and cannabinoid drugs are widely used to treat disease or alleviate symptoms , but their efficacy for specific indications is not clear .
OBJECTIVE To conduct a systematic review of the benefits and adverse events ( AEs ) of cannabinoids .
Analgesic effect of delta-9-tetrahydrocannabinol.
A preliminary trial of oral delta-9-tetrahydrocannabinol ( THC ) demonstrated an analgesic effect of the drug in patients experiencing cancer pain .  Placebo and 5 , 10 , 15 , and 20 mg THC were administered double blind to ten patients .  Pain relief significantly superior to placebo was demonstrated at high dose levels ( 15 and 20 mg ) . At these levels , substantial sedation and mental clouding were reported
Most trials showed improvement in symptoms associated with cannabinoids but these associations did not reach statistical significance in all trials .
There was an increased risk of short-term AEs with cannabinoids , including serious AEs .
Common AEs included dizziness , dry mouth , nausea , fatigue , somnolence , euphoria , vomiting , disorientation , drowsiness , confusion , loss of balance , and hallucination .
CONCLUSIONS AND RELEVANCE There was moderate- quality evidence to support the use of cannabinoids for the treatment of chronic pain and spasticity .
There was low- quality evidence suggesting that cannabinoids were associated with improvements in nausea and vomiting due to chemotherapy , weight gain in HIV infection , sleep disorders , and Tourette syndrome .
Cannabinoids were associated with an increased risk of short-term AEs
IMPORTANCE Cannabis and cannabinoid drugs are widely used to treat disease or alleviate symptoms , but their efficacy for specific indications is not clear .
OBJECTIVE To conduct a systematic review of the benefits and adverse events ( AEs ) of cannabinoids .