In terms of law enforcement issues, roadside sobriety tests have not been validated for marijuana use, and plasma levels of the drug drop within minutes of use. “The alcohol model works well with alcohol, but cannabis is not alcohol.”
, professor of epidemiology (psychiatry) at Columbia University, New York, talked about trends of cannabis use in the United States. “Looking at states before and after legalization, we see that there is an increase in both cannabis use and cannabis disorders in adults.” Adolescents, however, are not smoking more, and “Kids are just not socializing; they are in their bedrooms with their smartphones. Depression is increasing in teens, but substance abuse is not.”
The last speaker was, a professor of psychiatry at Yale University, who talked about cannabis and psychosis. He defined three distinct relationships: acute transient psychosis that resolves fairly quickly, acute persistent psychosis that takes days or weeks to resolve, and psychotic reactions that are associated with recurrent psychotic symptoms. Studies suggest that those who have a psychotic reaction to marijuana are at elevated risk of being diagnosed with schizophrenia later, and that timing of exposure to marijuana may be important.