A forced dose, stepwise, upward titration of one week each of 5, 10, and 20 mg fluoxetine/placebo will occur at visits 4, 5, and 6. The treating physician may modify this titration schedule in response to emergent side effect following routine practice standards. Participants will remain on their visit 6 doses of fluoxetine/placebo until the study's final visit, unless side effects necessitate some downward titration.