Clostridium perfringens, the third most common cause of foodborne illness in the United States (1), most often causes a self-limited, diarrheal disease lasting 12-24 hours. Fatalities are very rare, occurring in <0.03% of cases (1). Death usually is caused by dehydration and occurs among the very young, the very old, and persons debilitated by illness (2). On May 7, 2010, 42 residents and 12 staff members at a Louisiana state psychiatric hospital experienced vomiting, abdominal cramps, and diarrhea. Within 24 hours, three patients had died. The three fatalities occurred among patients aged 41-61 years who were receiving medications that had anti-intestinal motility side effects. For two of three decedents, the cause of death found on postmortem examination was necrotizing colitis. Investigation by the Louisiana Office of Public Health (OPH) and CDC found that eating chicken served at dinner on May 6 was associated with illness. The chicken was cooked approximately 24 hours before serving and not cooled in accordance with hospital guidelines. C. perfringens enterotoxin (CPE) was detected in 20 of 23 stool specimens from ill residents and staff members. Genetic testing of C. perfringens toxins isolated from chicken and stool specimens was carried out to determine which of the two strains responsible for C. perfringens foodborne illness was present. The specimens tested negative for the beta-toxin gene, excluding C. perfringens type C as the etiologic agent and implicating C. perfringens type A. This outbreak underscores the need for strict food preparation guidelines at psychiatric inpatient facilities and the potential risk for adverse outcomes among any patients with impaired intestinal motility caused by medications, disease, and extremes of age when exposed to C. perfringens enterotoxin.