Q & A: Fluoxetine Over the Long Term

Q: I have a patient with bulimia nervosa who has been receiving fluoxetine for about 6 months. She is doing well, but how long should she stay on the drug? (LM, Fort Wayne, IN)

A: Fluoxetine is an effective treatment for such patients. In a recent controlled study of 232 patients who received fluoxetine or placebo, those who responded to acute treatment with the antidepressant had an improved outcome. When treatment is continued, they also have a decreased likelihood of relapse.

Steven J. Romano, MD and colleagues compared the safety and efficacy of treatment with fluoxetine versus placebo in preventing relapse of bulimia nervosa during a 52-week period after successful acute treatment with fluoxetine (Am J Psychiatry 2002; 159:96). Patients who met DSM-IV criteria for bulimia nervosa (purging type) were assigned to single-blind treatment with 60 mg/day of fluoxetine.

After 8 weeks of treatment, those who had a 50% or greater decrease from baseline in vomiting episodes during one of the two preceding weeks were randomly assigned to receive 60 mg/day of fluoxetine or placebo and then were monitored for relapse for up to 52 weeks. The criterion for relapse was a return to baseline vomiting frequency persisting for 2 consecutive weeks.

Patients treated with fluoxetine showed a longer time to relapse than placebo-treated patients. Other analyses, including frequency of binge eating episodes, Clinical Global Impression severity, and Yale-Brown-Cornell Eating Disorder Scale score, indicated that fluoxetine treatment was statistically superior to placebo. Attrition was high in this study, especially during the first 3 months after patients were randomly assigned to treatment groups.

Although patients treated with fluoxetine had a significantly lower rate of relapse, symptoms did retun over time. Thus, fluoxetine may need to be paired with other therapies, such as CBT, to maintain a lasting effect.