The consequences of marijuana use on intrapersonal and interpersonal functioning in black and white adolescents.

We examined the effects of marijuana use on adolescent personality, attitudinal, and behavioral attributes, perceived parent-adolescent relations, and perceived peer factors. Volunteer high school students (292 Blacks, 401 Whites) of middle-class backgrounds filled out questionnaires in their classrooms first when they were in the 9th and 10th grades and again 2 years later when they were in the 11th and 12th grades. Results suggest that regular use of marijuana may lead to lower achievement, increased tolerance of deviance, and more deviant behavior, and greater rebelliousness. Regular use also appears to interfere with adolescents' relationships with their parents and to lead them to associate with more deviant and drug-using friends. The consequences of marijuana use for intrapersonal and interpersonal functioning were for the most part similar in the different sex and age groups, although there were some ethnic differences.