This document provides information about drug use and the human body. It begins with contact information for Joe Keil and his website. It then presents several statistics about drug use in the United States and specific cities. Next, it defines different types of drugs and drug use. The document continues by explaining key body systems impacted by drugs and how homeostasis works to maintain balance. It concludes with descriptions of how drugs interact with the nervous system, concepts of drug absorption and elimination, and types of combined drug effects.