How to Taper Fluoxetine
For patients on fluoxetine 20 mg daily, reduce to 10 mg every other day for 1–2 weeks, then stop completely, with follow-up within 2–4 weeks to assess for discontinuation symptoms. 1
Why Fluoxetine Rarely Requires a Formal Taper
Fluoxetine has an elimination half-life of 4–6 days after chronic dosing, and its active metabolite norfluoxetine has a half-life of 7–16 days, creating a built-in "self-taper" that protects against abrupt withdrawal symptoms. 2, 3
Abrupt discontinuation of fluoxetine in a randomized, placebo-controlled trial of 395 patients showed no clinically significant discontinuation syndrome, with only mild, self-limited dizziness in a small percentage of patients. 4
Fluoxetine offers a safety advantage over shorter-acting SSRIs (such as paroxetine or sertraline) with respect to treatment interruption and may be a better choice for patients likely to miss doses. 4
Recommended Tapering Protocol for Standard Doses
For patients on 10 mg daily, reduce to 10 mg every other day for 1–2 weeks, then discontinue. 1
For patients on 20 mg daily, reduce to 10 mg daily for 1–2 weeks, then to 10 mg every other day for another 1–2 weeks before stopping. 1
Schedule follow-up within 2–4 weeks after complete discontinuation to monitor for any delayed withdrawal symptoms or relapse of underlying depression/anxiety. 1
Special Considerations for Long-Term or High-Dose Use
Patients on fluoxetine for more than 1 year or at doses above 20 mg daily may benefit from a more gradual taper (e.g., reducing by 10 mg every 2–4 weeks) to minimize risk of relapse, even though pharmacokinetic withdrawal is unlikely. 5
For patients with a history of severe depression or multiple relapses, integrate cognitive-behavioral therapy and stress-management strategies during and after discontinuation to reduce relapse risk. 1
Monitoring for Discontinuation Symptoms
Monitor for anxiety, insomnia, irritability, dizziness, nausea, and paresthesias at each follow-up visit, although these are uncommon with fluoxetine compared to other SSRIs. 5
If withdrawal symptoms emerge, slow the taper by returning to the previous dose for 1–2 weeks before attempting a more gradual reduction. 5
The taper rate must be determined by the patient's tolerance, not a rigid schedule, and pauses are acceptable when symptoms emerge. 5
Common Pitfalls to Avoid
Do not substitute another SSRI or SNRI during fluoxetine discontinuation unless there is a clear clinical indication for switching antidepressants, as this introduces unnecessary complexity. 5
Do not rush the taper in patients with comorbid anxiety disorders or panic disorder, as these patients may require longer tapers (4–8 weeks) despite fluoxetine's long half-life. 3
Avoid abrupt discontinuation in patients on doses above 40 mg daily or those with a history of severe withdrawal reactions to other antidepressants, even though fluoxetine is generally safe to stop abruptly. 5, 4
Alternative Dosing Strategies Based on Pharmacokinetics
Once-weekly dosing of fluoxetine (10–60 mg) has been used successfully as maintenance therapy in panic disorder, demonstrating that the long half-life allows for flexible dosing schedules. 3
Every-third-day dosing of fluoxetine 20 mg has been shown effective in major depression after an initial 4-week daily dosing period, though higher daily doses (40 mg) reduce relapse rates compared to lower doses. 6
These alternative schedules can serve as intermediate steps during tapering for patients who experience anxiety about complete discontinuation. 3, 6
When to Refer or Seek Specialist Input
Patients with unstable psychiatric comorbidities (e.g., bipolar disorder, active suicidal ideation) should have specialist involvement during any antidepressant taper. 5
Patients with co-occurring substance use disorders or a history of severe withdrawal reactions to other antidepressants may benefit from closer monitoring and slower tapers. 5