It is often advised that patients who have ingested an overdose of antidepressants (AD) or antipsychotics (AP) are monitored with continuous ECG for minimum of 12-24 hr. These patients are often observed in an ICU. Our aim was to identify the number of patients with AD and/or AP overdose without adverse signs at hospital admission that turned out to need intensive care treatment. The effect of the antidepressants overdose risk assessment (ADORA) system was evaluated in patients with antidepressant as well as antipsychotic overdose. Our hypothesis was that patients with low ADORA do not need intensive care treatment. This retrospective study was conducted in adult patients admitted to the ICU at Odense University Hospital after an overdose with AP and/or AD between 1 January 2009 and 1 September 2014. Patients with predefined adverse signs in the emergency department were excluded due to obvious need of intensive care. Of the 157 patients included, 12 patients (8%) developed events during the ICU stay. Only 3 patients received intubation, vasoactive drugs and/or dialysis. None developed ventricular dysrhythmias. There were no fatalities. All the patients with low-risk assessment by ADORA within the first 6 hr did not develop events within the first 24 hr after hospital admission. The vast majority of patients with AD and/or AP overdose and no adverse signs at admission did not require intensive care treatment. Low-risk ADORA identified patients with antidepressant as well as antipsychotic overdose who would not require initial intensive care treatment. This is the first time the ADORA system has been evaluated in patients with antidepressant as well as antipsychotic overdose.The Danish Poison Information Centre (DPIC) provides overthe-phone counselling for the general public and healthcare professionals regarding all acute poisonings. DPIC registers the number of enquiries made and the number of substances included in each case. Antidepressants (AD) and antipsychotics (AP) account for 6.3% and 4.9% calls, respectively. According to DPIC, selective serotonin reuptake inhibitors (SSRI) were the most common AD and chlorprothixene the most common AP [1].Side effects of AD and AP overdose potentially include life-threatening complications like hypotension, ventricular dysrhythmias or seizures [2][3][4][5][6][7]. Both drugs pose a risk of QRS and QTc interval prolongation, tachycardia and hypotension [2][3][4]6]. AP more frequently causes QTc interval prolongation than AD, with ventricular fibrillation and torsades de pointes being two possibly fatal complications of QTc interval prolongation [8,9]. AD is shown to more commonly cause seizures than AP [5].The antidepressant overdose risk assessment (ADORA) criteria were first described in 1995 by Garrett E. Foulke [4]. The criteria describe the early complications of AD overdose and include QRS interval >0.1 sec., cardiac dysrhythmias, altered mental status (Glasgow Coma Scale <14), seizures, respiratory depression (<8 breaths/min. or assisted ventilation) and...