Aims: Limited information is available on the source of medications taken in intentional drug overdoses (IDOs). The present study aimed to investigate the proportion of patients who engaged in IDOs with current prescriptions and the proportion of those that used their medicines in overdose acts, as well as the factors associated with patients who do so.

Methods: The registration systems of three hospital emergency departments participating in the Irish National Registry of Deliberate Self Harm were screened over a continuous 6-month period and a consecutive series of 299 IDO presentations were identified.

Results: Most of the IDO presentations involved female patients (59.9%) and half (50.4%) had a previous history of self-harm. The prescription of psychotropic drugs was associated with the use of these drugs in IDOs, particularly minor tranquilizers. Having a prescription of a minor tranquilizer increased the risk of using prescribed psychotropic drugs in IDOs even when controlling for other factors.

Conclusion: These findings highlight the importance of considering the risk of IDO among patients who are prescribed minor tranquilizers.