Affective disorders, or mood disorders, are often diagnosed in people who use or are addicted to psychoactive substances. Symptoms of substance use disorder can mimic symptoms of both depression and mania. For example, acute alcohol intoxication or stimulant intoxication can cause symptoms of mania or hypomania, and withdrawal symptoms often manifest with dysphoria and depression. Treatment of comorbid mood disorders affects the further course of the disease and treatment prognosis. Why does this happen? Why is it important to diagnose depression, bipolar disorder? Is it correct to screen for...