Quetiapine Augmentation for Treatment-resistant PTSD

This is a two-site study designed to evaluate the efficacy and safety of quetiapine augmentation of paroxetine treatment in veterans with PTSD who have failed to respond to paroxetine treatment. In Phase I, eligible patients will take open-label paroxetine (up to 60 mg daily) for 8 weeks. Patients who are refractory (less than 30% reduction in CAPS scores or a minimum CAPS score of 50 at week 8) and have PTSD symptoms of at least moderate severity on CGI-S will be eligible for the second phase. In Phase II, patients will continue taking open-label paroxetine and will be randomized to the addition of quetiapine (up to 800 mg daily) or placebo for 8 weeks in a double-blind fashion.