Participant suicidal ideation will be assessed weekly with the C-SSRS, and daily if results indicate development of suicidal ideation. Weekly evaluations will include measures of symptoms of PTSD, depression, anxiety, sleep quality, general functioning, and responses to cannabis. During each evaluation, actigraph data will also be downloaded and a urine-dip EtG test will be performed. Analysis of blood/urine cannabinoids will be conducted after cessation periods, in addition to weekly urine drug screening for substances other than cannabis. At Baseline and end of Stage 1, Cessation 1 and end of Stage 2, additional blood samples will be collected for analysis of inflammation markers. At the end of Stage 1 and 2, endpoint measures will be administered; an independent rater will evaluate symptoms of PTSD on the CAPS-5 via telemedicine, and self-reported symptoms of anxiety, depression, withdrawal, sleep quality, and psychosocial functioning will be assessed.