Drug Use Disorders: Biological Factors

Drug use disorders are characterized by pathological substance use that appears outside of the user’s control, occurs in situations that are potentially hazardous, results in functional impairment, and produces physiological symptoms of dependence. Although psychosocial factors contribute to substance use onset, biological factors (both neurological and genetic) are involved in the progression from initial to problematic use. This entry provides a brief overview of how the brain communicates, the brain structures affected by drugs of abuse, how chronic use affects those structures, and the role of genetics in susceptibility to pathological use.