The Teenage Mind

The internal experience of the young adult.

Jann Gumbiner, PhD, is a licensed psychologist and clinical professor at the University of California, Irvine College of Medicine. See full bio

July 6, 2009, Addiction

How Much Pot Is Too Much Pot?

When does substance use become substance abuse?

Marijuana is generally thought of as a soft drug. It is perceived as less harmful than alcohol. But, like anything from a glass of wine to doughnuts, it is possible to overindulge. So, how much pot is too much pot?

Are you smoking too much when you can't get out of bed to go to class? Are you smoking too much when you light up daily but are still getting straight A"s? How do you know when you are smoking too much pot?

There is no easy answer to this question. "Too much pot" will vary from individual to individual. Ryan can light up and study physics every night. Sarah gets the munchies, over eats, and falls asleep. The amount and type of pot will affect different people differently.

When does substance use become substance abuse? The Diagnostic and Statistical Manual of Mental Disorders, DSM-IV-TR (2000), which is the most widely used psychiatric classification system, lists 8 Cannabis Disorders. They are: Cannabis Dependence, Cannabis Abuse, Cannabis Intoxication, Cannabis Intoxication Delirium, Cannabis-Induced Psychotic Disorder, With Delusions, Cannabis-Induced Psychotic Disorder, With Hallucinations, Cannabis-Induced Anxiety Disorder, and Cannabis-Related Disorder Not Otherwise Specified. The diagnostic criteria for Cannabis Abuse, for example, are:

recurrent use resulting in failure to fulfill major role obligations at work, school, or home
recurrent use in situations that are physically harmful, like driving a car
recurrent substance-related legal problems
continued substance abuse despite recurrent social or interpersonal problems exacerbated by the effects.

In other words, Cannabis Abuse is considered a mental disorder when it impairs social or occupational functioning. In a teenager or college student, this usually takes the form of poor school performance, change of friends, and/or conflict with the law. For example, if a student is unable to get out of bed and go to class and her grades drop, then she is smoking too much pot. If a man is breaking the law by growing and selling to buy pot, then he is smoking too much. Simply put, when marijuana is interfering with daily life it is too much.

American Psychiatric Association. 2009. Diagnostic and statistical manual of mental disorders (4th ed., text revsion). Washington, DC: Author.