Impulsivity is a behavior in everyday life of mentally healthy individuals. But in some cases the degree of impulsivity begins to create negative effects on one's life and acquires pathological connotation. Two clinical entities in which can be observed a high degree of impulsivity is Attention Deficit Hyperactivity Disorder (ADHD) and Addictive disorders. In these disorders, both impulsive act and impulsive choice are observed. According to some researchers, genetic factors are involved in the control of impulsivity. The impulsive choice, in the sense of delay discounting, may be an intermediate phenotype or endophenotype that contributes to vulnerability with respect to specific disorders in which impulsivity plays a central and decisive role. Another group of researchers argue that ADHD is one of the expressions of a more generalized disorder, known as reward-deficiency syndrome. In this syndrome, it is included increased frequency of addictive disorders.
On the other hand, some researchers argue that ADHD in adolescence does not increase the likelihood of developing dependencies, when it is not accompanied by comorbidity of conduct disorders. Regarding the use of substances, there have been conflicting views in relation to etiopathogenesis of impulsivity observed in the addicted patients and whether this impulsivity precedes or follows the onset of substance use. The element that links ADHD with impaired preoccupation with gambling and has been studied most is also impulsivity. Some researchers theorize that ADHD mediates with the element of impulsivity in the development of disordered involvement with gambling in some patients. The positive correlation between impulsivity and addiction to gambling arises, whether behavioral scales or questionnaires about personality have been used. Moreover the higher measured impulsivity of the patient, the more serious are the symptoms of dependence. Abnormalities in neurotransmitter systems have been found both in patients with dependence on gambling, as well as in patients with impulsive behavior. It seems that impulsivity in these players is part of their personality and not a transient behavior.
The variety of views that exists and the debate surrounding this issue reflects the multidisciplinary nature of the phenomenon of impulsivity, when found in dual diagnosis of Attention Deficit/Hyperactivity Disorder and Addictive Disorder. It is important for patients with ADHD or any form of addictive disorder, presenting for treatment, to assess the degree of their impulsivity and to investigate the possible comorbidity with other mental health problems, in which impulsivity plays a central role.