This document summarizes the effects of various drugs on the body and behavior. It discusses how drugs affect neurotransmitters in the brain like dopamine, serotonin, and endorphins. Specific drugs covered include cocaine, ecstasy, marijuana, heroin, alcohol, caffeine, nicotine, and methamphetamine. Short-term and long-term effects are described for each drug. The document also discusses how drug addiction develops in the brain and provides tips to prevent drug use.