The article attempts to construct a typology to the use of psychoactive drugs and the study of the various factors linked to their use, whether heavy or regular. The results draw on the exploitation of databases containing medicines presented for reimbursement by medical insurance in the Nord - Pas-de-Calais region. In 2007 and 2008, 20.7% of the insured population (764,650 people) benefited from reimbursements for this type of medication. Among the beneficiaries, about a third (30.5%) had an intense consummation. Age, the CMUs benefits and the fact that a person is or not followed by a psychiatrist are the most influential variables on the intensity and the regularity of intake. The observed regularity of the recourse to benzodiazepines does not conform with the current recommendations.