Addictive substances most commonly detected illicit drug Most Used Addictive Drugs NIDA Most Commonly Abused Drugs certain drugs most abused illicit drugs for teens Addictive substances drug Addictive substances the most commonly used illicit drug are more likely to become addicted NIDA NIDA illegal substances Drugs the most commonly used Most Used Addictive Drugs The National Institute On Drug Abuse Addictive substances favored illegal drug of Americans most popular illegal drug most widely used illicit substance NIH Most Commonly Used Addictive Drugs Addictive substances addictive substances most commonly abused drug, addictive substances Addictive substances popular drugs National Institute on Drug Abuse more Americans use marijuana than any other drug effects vary National Institute on Drug Abuse