Between 1993 and 2004, patients with antidepressant poisoning admitted to an emergency department (ED) were analysed retrospectively with regard to demographics, clinical findings and treatment attempts. Age, gender, suicide attempts, classification of antidepressants, Glasgow Coma Scale (GCS) score, ECG findings, need for endotracheal intubation, follow-up period and Antidepressant Overdose Risk Assessment (ADORA) criteria were analysed by SPSS software. A total of 356 antidepressant poisoning cases were evaluated. Tricyclic antidepressants (TCA), especially opipramol and amitriptyline, were the most common agents (58.4%). The most frequent ECG finding was sinus tachycardia (40.7%, n=145). Endotracheal intubation was required in 9.6% of cases. Patients with TCA ingestion had a longer observation time in the ED, abnormal ECG findings, abnormal physical examination findings and more ADORA criteria, than patients who ingested selective serotonin re-uptake inhibitors (SSRI) (P = 0.008, P = 0.008, P < 0.001, P < 0.001). It was found that the patients who ingested TCA (P = 0.001), poisoned with amitriptyline (P = 0.001), patients with GCS scores of 8 and less (P = 0.001), patients with two or more ADORA criteria (P = 0.001), with seizures (P = 0.001), with abnormal ECG (P = 0.012), and patients with a history of two or more suicide attempts were intubated more frequently. Suicide attempts, classification of the antidepressant, ECG findings, seizure, GCS score and number of detected ADORA criteria affect the need for intubation in patients with antidepressant poisoning.