According to the U.S. Department of Health and Human Services' Substance Abuse and Mental Health Services Administration, roughly 20 million Americans use illicit drugs annually. Approximately 10 per cent of teens between the ages of 12 and 17 use illicit drugs, and this number jumps to 20 per cent for young adults between the ages of 18 to 25. ""The Truth About Drugs, Second Edition"" provides a complete and informative guide to drugs and drug abuse. The hard facts and personal testimonies will help teenagers make an informed decision about drugs. New and revised entries of this title include: The biology of addiction; Causes of drug abuse; Depression and drugs; Drug testing; Drugs and smoking; Families and drug abuse; Gangs and drug abuse; International drug use; Marijuana; Natural drugs; Over-the-counter drugs; Rehabilitation and treatment; and, School performance and drug abuse.