Acute drug intoxication has recently become an important issue in the social and clinical areas. There are various complications associated with acute drug intoxication such as pneumonia, but the process is was not fully understood. The aim of this study was to analyze our cases of pneumonia associated with acute drug intoxication and to determine the associated risk factors.

Forty four cases out of 237 patients, who were acute drug intoxicated from May 2000 to Feb. 2005, were diagnosed with pneumonia at the Konyang University hospital. These cases were analyzed by a retrospective review of their medical records.

The incidence of pneumonia in acute drug intoxication was 18.6%. There was no gender difference in terms of the incidence, but the age group with the highest incidence was in the 5^th decade (22.5%) followed by the 7^th decade (17.9%). Most common drug of associated with pneumonia was organophosphate insecticides, and the others were herbicides. Suicidal attempts were the most common motive of intoxication. The incidence of pneumonia was increased in old age (β=0.128, p<0.05). A drowsy or comatous mental status was an independent risk factors of pneumonia (β=-0.209, p=0.006). A longer hospital duration was also a risk factor for pneumonia (β=0.361, p<0.001). The intubated state, intensive care unit care and longer duration of admission correlated with the course of pneumonia in acute drug intoxicated patients (p<0.05). The culture study revealed MRSA to be most common pathogen.

The incidence of pneumonia associated with acute drug intoxication was higher in the older aged patients, those with a decreased initial mental status and a longer hospital duration. The number of days in the intensive care unit and intubation were associated prognostic factors for pneumonia in acute drug intoxication patients.