The attention deficit is the main symptom of the Attention Deficit Hyperactivity Disorder (ADHD) in adults. This diagnosis is difficult in adults and comorbidity with substance abuse (SA) is high. As ADHD influences negatively the prognosis of the patients with SA, it is important to treat the ADHD in individuals with DS. Furthermore, it is common the use of substances to relieve ADHD and its comorbidities's symptoms.

It is known the paradoxical effect of amphetamines in individuals with ADHD and it was also described with cocaine. This characteristic is an important clinical clue to the diagnosis of ADHD and it is a predictor of a positive response to the therapeutics.

It is intended to approach the issues related to the psycopathology, differential diagnosis, prognostic and therapeutic implications when there is comorbidity between ADHD and SA in the adult.

Therapeutic implications of the comorbidity between ADHD and SA.

Analyses of a clinical case and a non-systematic review of the literature was made.

A 23-year-old woman, lawyer, has the diagnosis of ADHD since childhood. She regularly used cocaine for the last 2 years, without doing any medication, as she felt quiet, relax and focused, being more productive at work. The treatment with prolonged-release methylphenidate allowed to stop the use of cocaine without a recurrence of cognitive symptoms.

The ADHA is an independent risk factor to the SA; The early detection and treatment of ADHD helps to prevent the substance abuse;