The United States as a whole is battling an opioid epidemic, but certain states are harder hit by drugs than others. Colorado, for example, has the highest percentage of teenagers and adults who use illicit drugs, while West Virginia has the most overdose deaths per capita, reports WalletHub. The site ranked the 50 states and the District of Columbia on these factors and others, including drug arrests and opioid prescriptions, to find the states with the biggest drug problems. The top 10: