OBJECTIVE: Generalized anxiety disorder (GAD) is a prevalent and debilitating psychiatric condition of adolescence. Two effective forms of treatment are cognitive behavioral therapy (CBT) and selective serotonin reuptake inhibitors (SSRIs). This pilot study examined changes in brain function following each type of treatment in GAD. METHOD: Subjects were 14 youths with GAD (7 had CBT, 7 received fluoxetine) and 10 age- and gender-matched healthy peers. Functional magnetic resonance imaging (fMRI) scans were acquired before and after treatment for patients and over two comparable time points for controls. During fMRI acquisition, a probe detection task with emotional (angry, happy) and neutral faces allowed for assessment of neural response to threat. Following previous research, region of interest analyses were performed in the right ventrolateral prefrontal cortex (VLPFC). RESULTS: fMRI results showed increased right VLPFC activation, relative to controls, in the medication (t(15) = 3.01, p < 0.01) and CBT (t(15) = 3.22, p < 0.01) groups following treatment. CONCLUSIONS: This study shows significant increase in right VLPFC activation in response to angry faces following treatment with CBT or fluoxetine for GAD. This is consistent with previous research indicating that the VLPFC may facilitate effective responding to underlying neural correlates of anxiety in other brain regions, such as the amygdala.