It’s not necessarily helpful to label one substance as more addictive than another, because a person’s drug of choice is what causes them problems personally. However, alcohol, opiate painkillers and heroin abuse are particularly pervasive because they can cause such severe physical dependence. The withdrawal symptoms and initial detox phase are usually too extreme to attempt alone with these illnesses.
That said, people can develop severe substance use disorders with any psychoactive drug. The physical sensations in the mind are incredibly powerful, and they can lead people to become terribly trapped in the cycle of addiction.