Background: Many acute poisoned patients have co-ingested alcohol in the emergency department (ED). This study aimed to estimate the blood alcohol concentration (BAC) of acute poisoned patients who visited an ED by age and gender distribution and to determine whether it is possible to obtain self-reports of alcohol ingestion among poisoned patients. Method: A retrospective medical chart review was conducted for all patients who visited the ED with acute poisoning between January 2004 and February 2008. Data regarding the patient's age, gender, BAC, self-reported alcohol ingestion, poison ingested, time elapsed since poison exposure, presence of suicide attempts, and self-reported alcohol ingestion were collected. Patients were classified into two groups based on serum alcohol levels (=10 mg/dl, >10 mg/dl). Results: Of the 255 subjects, 88 subjects (34.5%) were included in the non-alcohol group and 167 subjects (65.5%) were included in the alcohol group. 227 subjects (89.0%) showed suicide intention. Using the 201 subjects who completed the self-report of alcohol ingestion, self-report resulted in 96.6% sensitivity and 86.7% specificity for the assessment of alcohol ingestion. The positive and negative predictive values for self-report were 91.2% and 94.7%, respectively. The median (interquartile range) BAC of the 97 males in the sample was 85.0 (10.0-173.5) mg/dl, and that of the 158 females was 32.0 (4.0-137.5) mg/dl (p = 0.010). The distribution of age in the groups was significantly different between the alcohol and non-alcohol groups (p = 0.035), and there was a significant difference in the mean BAC with respect to age for males (p = 0.003). Conclusion: This study showed that over two-thirds of patients presenting with acute poisoning had a BAC > 10 mg/dl. Most of patients visited by suicide attempt. Males had a higher BAC than did females. Self-reported alcohol ingestion in acute poisoned patients showed high sensitivity and specificity. [ABSTRACT FROM AUTHOR]