What are some addictive drugs? what makes a drug addictive?

Not a simple ?: Addiction has become more of a legal and social term. Medically, we speak of "substance use disorders." Drugs which cause physical dependency are alcohol, barbiturates, benzodiazepines, some other sedatives, and opioid pain medication, and all can also lead to addiction. Amphetamines, cocaine, hallucinogens, inhalants may not cause physical dependency, but compulsive use can constitute addiction.