Three common mental disorders that can lead to substance use disorder through self-medication are depression, anxiety and Posttraumatic Stress Disorder. Depression disorders include bipolar disorder, seasonal affective disorder, psychotic depression, postpartum depression and persistent depressive disorder. A few common anxiety disorders are phobias, social anxiety and generalized anxiety disorder. And with PTSD, a person experiences negative mental health effects as the result of past traumatic experiences. Whether it’s to mitigate panic attacks caused by anxiety or numb suicidal thoughts caused by depression, substance use as self-medication may lead to addiction.