WASHINGTON -- The White House drug czar said in a warning to parents yesterday that depressed teens are medicating themselves with marijuana, running risks of even deeper depression.
A new report by the Office of National Drug Control Policy said that frequent marijuana ingestion doubles a teen's risk of depression and anxiety, based on data compiled from published studies.
The report, timed to be released during Mental Health Awareness Month, cited a study that marijuana use increases the risk of developing mental disorders later in life by 40 percent.
"In short, marijuana makes a bad situation worse," said John P. Walters, director of the drug control policy office.
Critics said the administration is trying to scare teenagers by exaggerating the dangers.
"When you start convincing young people and their parents that marijuana is the cause of problems rather than the symptom of them, you can get into real problems," said Bruce Mirken, spokesman for the Washington-based Marijuana Policy Project, which advocates decriminalization of the drug. "It may cause people, parents, teens and counselors to overlook the real cause of the problem."
Some addiction experts said that the report stretches evidence by implying a causal link between smoking pot and developing mental illness that did not previously exist, even if there is consensus that depression is a risk factor for drug use.
A British government advisory group concluded in a report last month that there is not convincing evidence to show "a causal relationship between the use of cannabis and the development of any affective disorder."
Pushed on the report's claim that "using marijuana can cause depression and other mental illnesses" at a news conference, Walters demurred and acknowledged that there is no proof that one leads to another.
"Marijuana makes things worse, not only for young people in general, but it particularly makes things worse with regard to mental health and depression," he said.
Among experts inside and outside the government, opinions are mixed on the relationship between teens, depression and marijuana.
"Both conditions could be related to something else," said Dr. Victor Reus, a psychiatrist at the University of California, San Francisco, in an interview. "Depressed teens are more likely to exercise less, stay indoors and watch TV. Take your pick as to which one is causal."
Dr. Nora D. Volkow, director of the National Institute on Drug Abuse at the National Institutes of Health, said many kids who smoke cannabis never become depressed. She said evidence indicates genetic factors make some teens more vulnerable to mental disorders so that marijuana can trigger their onset.
James Hohmann writes for the Los Angeles Times.