According to a study conducted at Case Western Reserve University School of Medicine, among teens with substance use disorders, those who also have social anxiety disorder begin using marijuana at a mean age of 10.6 years — an average of 2.2 years earlier than teens without anxiety.
According to the authors, there was no clear evidence showing whether agoraphobia came before or after either marijuana use or the first drink.
A limitation of the study, according to the research team, was that 128 (66 percent) of the teens were juvenile offenders who had received court-referred treatment for their substance abuse. These findings might not generalize to a less severely addicted population.