This report provides a comprehensive overview of drug classification, encompassing stimulants, depressants, and other drug classes, along with their primary properties and associated harms. It details the various withdrawal stages and symptoms for different substances, including alcohol and stimulants, and outlines effective support strategies for clients undergoing withdrawal. The report further explores the spectrum of dependency, from experimentation to situational dependence and full addiction. Additionally, it examines poly-drug use, its definition, and the potential for dangerous drug interactions, including those involving prescription medications. The conclusion emphasizes the severity of drug-related harms and the importance of comprehensive support systems for individuals struggling with substance abuse.