Most will experiment and stop, or continue to use casually without significant problems. Some will use regularly, with varying degrees of physical, emotional and social problems. Some will develop a dependency and be destructive to themselves and others for many years. Some will die, and some will cause others to die.
Some people grow out of their use of alcohol and other drugs.
But since there is no certain way to predict which teenagers will develop serious problems, all use should be considered dangerous. Highest on the list are those teenagers with a family history of Substance Abuse problems. Although the use of some drugs has leveled off recently, the use of others has not. Those who begin to smoke or drink during their early teens are at particularly high risk. Most adolescents continue using the earlier drugs as they begin using still others.