To assess with which frequency subjects with intentional overdose of psychotropic drugs ingest their own psychotropic drug treatment, and whether prescription of a drug may be a factor influencing the choice of drugs used for the IDO.

Demographic characteristics, psychiatric history, and currently prescribed psychotropic drug treatment were collected for all the patients (n=1654) admitted to an emergency department (ED) for IDO with psychotropic drugs (anxiolytics, hypnotics, antidepressants, antipsychotics and mood stabilizers) over a period of 18 months.

Two-thirds of the patients ingested during the IDO at least one of their own prescribed psychotropic drugs. Compared with the subjects who had ingested psychotropic drugs not prescribed for them, they were more likely to have a history of psychiatric hospitalization (OR 4.2; 95%CI 3.1-5.5), of parasuicide (OR 2.5; 95%CI 1.9-3.3), to be a psychiatric outpatient (OR 3.9; 95%CI 3.0-5.1), and to present with a serious IDO (OR 2; 95%CI 1.4-2.9). Independently from age and psychiatric hospitalization history (i.e. the seriousness of psychiatric disorder), they ingested during the IDO more often antidepressants (OR 4.4; 95%CI 3.0-6.4), antipsychotics (OR 2.9; 95%CI 1.7-4.8) and mood stabilizers (OR 4.1; 95%CI 1.6-10.7). No association was found with prescription for overdose of benzodiazepine or paracetamol.

Prescription of the psychotropic drugs plays an important role in the choice of the drugs ingested for the IDO. It might make potentially “dangerous” drugs available for the patient. Physicians have always to balance the benefit of the treatment against the risk of drug overdose.