Depression and heavy drinking often show up together. So do anxiety and opioid use. When a mental health condition and a substance use disorder happen at the same time, that is dual diagnosis. It is common. In addiction treatment, two conditions at once is closer to the norm than the exception.

This matters for you or your loved one. Treating the addiction alone leaves the mental health condition untreated. Dual diagnosis treatment addresses both together, because one usually feeds the other.