Mounting evidence suggests that common genetic factors may predispose individuals to both mental disorders and addiction, or to having a greater risk of the second disorder, once the first appears. Stress, trauma like physical or sexual abuse and early exposure to drugs are common factors that can lead to addiction and to mental illness, particularly in those with underlying genetic vulnerabilities. Both drug and mental disorders affect some of the same areas of the brain. For example, the areas of the brain that react to drug use are the same as those circuits that react to reward processing and show abnormalities in specific mental disorders. Drug abuse and mental illness are developmental disorders. Drug abuse and mental illness often begin in adolescence or even childhood, which are periods when the brain undergoes dramatic developmental changes. Early exposure to drugs can change the brain in ways that increase the risk for mental illness, just as early symptoms of a mental disorder may increase vulnerability to drug abuse.

Institute of Mental Health

The National Institute of Mental Health mission of NIMH is to transform the understanding and treatment of mental illnesses through basic and clinical research, paving the way for prevention, recovery and cure. In support of this mission, NIMH generates research and promotes research training to fulfill the following four objectives: promote discovery in the brain and behavioral sciences to fuel research on the causes of mental disorders; chart mental illness trajectories to determine when, where and how to intervene; develop new and better interventions that incorporate the diverse needs and circumstances of people with mental illnesses; and strengthen the public health impact of NIMH- supported research.

Complementary Medicine

Many Americans use complementary and alternative medicine in pursuit of health and wellbeing. Defining complementary medicine is difficult, because the field is very broad and constantly changing. Complementary medicine is a group of diverse medical and health care systems, practices and products that physicians and the public do not generally consider a part of conventional medicine. Conventional medicine is medicine as practiced by holders of MD medical degrees, as medical doctors and DO as doctors of osteopathy degrees and by allied health professionals, such as physical therapists, psychologists and registered nurses. The boundaries between complementary medicine and conventional medicine are not absolute and specific complementary medicine practices may become widely accepted.
Most alternative medicines that Americans use are complementary. Alternative medicine refers to complementary medicine that replaces conventional medicine. Integrative medicine refers to a practice that combines both conventional and complementary medicine treatments that show safety and effectiveness.