Fluoxetine for Relapse Prevention After Weight Restoration: A Negative Trial
A newly weight-restored college student is heading back into the exact environment that fed her illness, and everyone wants to give her every advantage available — including a drug that an earlier, smaller trial suggested might help, and a later, larger, better trial found does nothing at all.
J.P., a 20-year-old woman, rows for her university's club crew team, or did until six weeks ago, when her coach quietly pulled her aside after a teammate raised concerns and the whole thing unraveled into a hospital admission neither of them saw coming that morning. She is a sophomore studying environmental engineering, the kind of student who color-codes her class notes, and by her own telling, the restriction started as exactly that same instinct turned on her own body — a project to optimize, tracked with the same rigor she brings to problem sets, until optimization became elimination. Six weeks of inpatient nutritional rehabilitation later, she has reached her target weight range, her labs have normalized, and discharge planning is now the actual work of the meeting.
The team is not naive about what discharge means for her specifically: she is returning to the same dorm, the same dining hall, and — pending her own decision, not yet made — potentially the same boat that first organized her relationship to food around performance and control. Everyone in the room wants to give her every real advantage available for the next several months, which is what puts fluoxetine on the table. An earlier, smaller trial (Kaye and colleagues, 2001) had suggested real promise for exactly this use — fluoxetine started after weight restoration, aimed specifically at relapse prevention rather than acute treatment — and for several years afterward it became common practice on that basis. But the larger, better-powered, placebo-controlled test of that same question came later: Walsh and colleagues' 2006 randomized trial, 93 patients, all receiving cognitive-behavioral therapy either with fluoxetine or with placebo, found no difference in relapse rates between the two arms over the year that followed. It is, by the field's own standard, a clean negative result — not underpowered, not confounded by inconsistent therapy, testing the exact question the team is asking about J.P. right now. The honest tension in the room isn't whether the trial was well-designed. It's whether "the best evidence found nothing" is the same thing as "there is nothing more we can offer her."
Discharge planning, day 41
I know the evidence is mixed, but she's walking back into the exact dorm, the exact dining hall, and possibly the exact boat that fed this illness in the first place. Kaye and colleagues found real signal for fluoxetine specifically as relapse prevention after weight restoration. Given what she's about to face, I'd rather offer her every reasonable advantage than withhold something on the strength of one later trial.
I want to be precise about what "one later trial" actually is here. Walsh and colleagues' 2006 randomized controlled trial tested this exact question — fluoxetine plus CBT versus placebo plus CBT, specifically for relapse prevention after weight restoration — in 93 patients, larger and more rigorously controlled than the earlier Kaye study. It found no difference in relapse rates between the two arms over a full year. That's not an absence of evidence; it's a direct, well-powered negative answer to the precise question we're asking about J.P. When a better trial directly supersedes an earlier, smaller one on the same question, I don't think we get to treat them as equally weighted options to choose between.
You're right that Walsh is the better-designed trial and that it directly answers this question — I'm not going to argue the pharmacology should override that. Where I'd usually look for daylight is a subgroup: a patient with real residual depression or anxiety might have an independent rationale for an SSRI regardless of what the relapse-prevention trial showed. But J.P.'s own inpatient workup didn't find a comorbid mood or anxiety disorder, so there's no separate door here to walk through. Her case doesn't have the exception; it's squarely inside the population Walsh studied.
What I'd actually propose instead of medication: put the same energy the room wants to spend on a fluoxetine trial into her outpatient CBT-E starting immediately at discharge, with explicit early sessions on the crew-team decision specifically, since that's a concrete, modifiable relapse risk the negative drug trial has nothing to say about either way.
Agreed: no fluoxetine at discharge, on the strength of Walsh et al.'s direct negative trial and the absence of any independent mood/anxiety indication in J.P.'s own workup. Outpatient CBT-E begins immediately, with early sessions specifically addressing the crew-team decision as a concrete relapse-risk factor.
Not agreed: whether to revisit medication automatically if J.P. develops depressive or anxiety symptoms during the vulnerable post-discharge period, or whether that would require a fresh workup each time rather than defaulting back to fluoxetine as "the eating disorder drug." The Attending Psychiatrist wanted a standing plan to reconsider medication quickly if her mood declines post-discharge, given how fast things unraveled the first time; the Eating Disorder Therapist preferred treating any future mood change as its own independent clinical question, worked up on its own terms rather than triggering an automatic fluoxetine reflex. Left open, to be decided by whoever sees her first if symptoms actually emerge.