Illegal drug use is becoming a major problem in the United States, with the Mayo Clinic estimating that 19.5 million people over the age of 12 use illegal drugs and 19,000 people die from illegal drug use in the United States each year. Medical billers and coders will, from time to time, encounter codes for illicit drug use, drug overdoses, and deaths related to drug abuse. However, the United States has, since 1970, launched what is arguably the longest violent war in U.S. history, the War on Drugs. What is this war and what impact is it having on the battle against illegal drug use in the United States? Read on to find out.