Surveys indicate that by grade 12, a majority of youth have tried both alcohol and marijuana. Drugs commonly used by youth are usually inexpensive and easily obtained. The effects of illicit drugs depend on the type of drug, its concentration, purity, method of ingestion, and characteristics of user and environment. Youthful users may be experimenters, compulsive users, or floaters (between the two groups). Compulsive users are dependent on drugs and have their personal/social functioning and health affected by them. Signs of drug use may include mood swings, depression, slowed speech, diminished alertness, weight loss or gain, and deterioration in social function or school performance. A physician or clergyman may be able to provide information on available treatment options once a child's drug use is discovered. Options may include detoxification, residential treatment, crisis intervention, day care, and outpatient treatment and counseling. Aftercare programs also are available. Parental participation in treatment and aftercare is important to program success. 15 references.