Twenty-nine pediatric injury patients (ages 10-18) at risk for PTSD were randomly assigned to receive either propranolol or placebo in a double-blind placebo controlled design. Medication was initiated within 12 hours of hospital admission. At 6-weeks, child PTSD symptoms and heart rate (HR) during trauma recall were assessed. We hypothesized that participants who received propranolol would report fewer PTSD symptoms and have lower heart rates than those who received placebo.