Use of an Antibiotic as an Enhancer for the Treatment of Social Phobia

This study examines whether an antibiotic, d-cycloserine (DCS), boosts the effectiveness of cognitive behavior therapy (CBT) for social anxiety. CBT has been shown to be effective for the treatment of social anxiety in children and adults, but even after treatment, approximately 40% may remain diagnosable. The antibiotic DCS has been shown to enhance the type of learning that is promoted by exposure therapy, a main component of CBT. This study will test whether DCS can improve the effectiveness of CBT for social anxiety. All participants will receive 12 weekly CBT sessions. In addition to receiving the CBT, participants will be randomly assigned (similar to a coin toss) to receive either DCS or a placebo (sugar pill). The pill will be taken 1-2 hours prior to each of the 12 CBT sessions. The pill is taken only on the 12 therapy days. Prior to receiving treatment, participants will be asked to: * participate in interviews to assess diagnosis and how they are doing including mood, degree of nervousness and behavior * have a physical examination, a urine test, and an electrocardiogram (EKG) * undergo tests involving problem-solving and memory * prepare and present a speech to a "virtual audience" using virtual reality goggles * undergo functional magnetic resonance imaging (fMRI) while performing tasks that involve looking at pictures, remembering things, testing reaction times, and making simple choices Those who have not improved by the end of the study will be offered standard antianxiety medication treatment for 1 to 3 months. If a participant does not wish to take medication, study clinicians will help him/her locate psychological care in the community. Participants will be asked to complete a follow-up assessment 3 months after their last CBT session.