Dual diagnosis (also referred to as co-occurring disorders) is a term for when someone experiences a mental illness and a substance use disorder simultaneously. Either disorder—substance use or mental illness—can develop first. People experiencing a mental health condition may turn to alcohol or other drugs as a form of self-medication to improve the mental health symptoms they experience. However, research shows that alcohol and other drugs worsen the symptoms of mental illnesses.
Information above from the National Alliance on Mental Illness (Click here to read more)