'Atypical' antidepressants in overdose - Clinical considerations with respect to safety

The 'atypical' antidepressants comprise a heterogenous class with wide variation in presentation and management during overdose, both when compared with each other and with more traditional agents. Further toxico-epidemiological data are required to make definitive predictions about the clinical effects of most of these agents in overdose. Here, however, we review the available information in a manner intended to benefit both prescribers and clinical toxicologists. Our conclusion is that there can be no generic response by medical practitioners as to the 'safety' of these new antidepressants. Though undoubtedly exhibiting fewer problems in specific areas than some of the older classes of agents (e.g. arrhythmias with tricyclic antidepressants) each nonetheless presents unique safety problems. We experienced great difficulty obtaining accurate information from the manufacturers about the animal toxicity data upon which their recommended human dose limits were set. This highlights the uncertainties involved with too readily making 'safety' claims about these agents. The decision to prescribe 'atypical' antidepressant medications alleged to be both efficacious and safe in overdose involves a medicolegal tension. This tension is between respecting patient autonomy through frank communication of the material risk of overdose and non-disclosure to avoid such harm.