How to Taper Paroxetine
Paroxetine should be tapered gradually by reducing the dose by the smallest increment possible (e.g., 2.5 mg or 10% of the current dose) at intervals of at least 1-2 weeks between each reduction, continuing this pattern down to very low doses before complete cessation to minimize discontinuation syndrome. 1
Understanding Paroxetine Discontinuation Risk
Paroxetine carries one of the highest risks for discontinuation syndrome among SSRIs due to its relatively short half-life and potent serotonin transporter inhibition. 1, 2 The FDA label explicitly warns that abrupt discontinuation can cause dysphoric mood, irritability, agitation, dizziness, sensory disturbances (including electric shock sensations), anxiety, confusion, headache, lethargy, emotional lability, insomnia, and hypomania. 3
The American Academy of Child and Adolescent Psychiatry identifies the full spectrum of withdrawal symptoms including:
- Somatic symptoms: dizziness, fatigue, lethargy, myalgias, chills, headaches, nausea, vomiting, diarrhea, sensory disturbances, paresthesias 1
- Psychological symptoms: anxiety, irritability, agitation, abnormal dreams 1
- Neurological symptoms: imbalance, vertigo 1
These symptoms typically emerge within 1-3 days of dose reduction and can be severe enough to compel patients to restart medication. 1, 4
Recommended Tapering Protocol
Step 1: Pre-Taper Planning
- Discuss the tapering plan with the patient before initiating, avoiding stressful life periods for discontinuation 1
- Consider adding cognitive-behavioral therapy during the taper to increase success rates 1
- Set realistic expectations that tapering may require several weeks to months, especially for long-term users 1
Step 2: Dose Reduction Strategy
Use hyperbolic (percentage-based) tapering rather than linear tapering. Recent evidence demonstrates that reducing paroxetine doses by fixed percentages (rather than fixed amounts) produces linear reductions in serotonin transporter occupancy, which minimizes withdrawal symptoms. 4
Specific reduction schedule:
- Reduce by 10% of the current dose (not the original dose) at each step 1
- Allow at least 1-2 weeks between each dose reduction 1
- For patients on 20 mg or higher, the smallest practical increment is 2.5 mg 1
Example taper from 20 mg:
- 20 mg → 17.5 mg for 1-2 weeks
- 17.5 mg → 15 mg for 1-2 weeks
- 15 mg → 12.5 mg for 1-2 weeks
- 12.5 mg → 10 mg for 1-2 weeks
- 10 mg → 7.5 mg for 1-2 weeks
- 7.5 mg → 5 mg for 1-2 weeks
- 5 mg → 2.5 mg for 1-2 weeks
- 2.5 mg → discontinue 1
Step 3: Final Phase Considerations
Do not stop at therapeutic minimum doses. Guidelines recommending tapers down to only therapeutic minimums (10-20 mg) show minimal benefit over abrupt discontinuation. 4 Continue tapering to doses much lower than therapeutic minimums (2.5 mg or less) before complete cessation. 4
Alternative frequency reduction: If withdrawal symptoms emerge during dose reduction, consider switching to frequency tapering—taking the medication every other day or every third day before complete cessation. 1
Managing Withdrawal Symptoms
If intolerable symptoms occur:
- Resume the previously prescribed dose 3
- Once symptoms resolve, restart the taper at a slower rate (e.g., 5% reductions instead of 10%, or longer intervals between reductions) 3
- Mild symptoms can be managed with reassurance that they are typically transient 2
Monitor closely during weeks 1-2 after each dose reduction for discontinuation symptoms including dizziness, headaches, nausea, insomnia, paresthesias, and anxiety. 5
The taper may need to be paused and restarted when the patient is ready, and should be slowed once reaching low dosages. 6 Tapers are considered successful as long as the patient is making progress. 6
Critical Pitfalls to Avoid
Never abruptly discontinue paroxetine except in extreme cases such as confirmed diversion or serious medical toxicity—even then, there is overdose risk at care transition points. 6 Sudden cessation is no more appropriate with paroxetine than with antihypertensives or antihyperglycemics. 6
Do not mistake withdrawal symptoms for relapse. Discontinuation syndrome can be misdiagnosed as depression recurrence, leading to unnecessary long-term medication continuation. 4 The key differentiator is timing: withdrawal symptoms emerge within 1-3 days of dose reduction, while true relapse typically occurs weeks to months later. 1
Avoid "cold referrals" to clinicians who have not agreed to accept the patient—this constitutes abandonment. 6 The prescribing clinician is obligated to either offer a comfortable tapering regimen or obtain agreement from another physician to provide care. 6
Special Populations
Patients taking tamoxifen: Consider switching to an alternative antidepressant with minimal CYP2D6 inhibition rather than continuing paroxetine, as paroxetine irreversibly inhibits CYP2D6 and may reduce tamoxifen efficacy. 3 If tapering paroxetine in this population, use the same gradual protocol but prioritize transition to a non-interacting agent.
Elderly patients: May be at greater risk for hyponatremia and SIADH during both treatment and tapering. 3 Monitor sodium levels if symptoms of hyponatremia develop.
Alternative: Switching to Fluoxetine
For patients with a history of severe SSRI discontinuation syndrome, consider cross-tapering to fluoxetine before discontinuation. Fluoxetine's long half-life (4-6 days) provides natural protection against withdrawal symptoms through a "self-tapering" effect. 5
Cross-taper protocol:
- Overlap paroxetine 10 mg daily with fluoxetine 20 mg daily for one week 5
- Monitor for serotonin syndrome in the first 24-48 hours (mental status changes, neuromuscular hyperactivity, autonomic hyperactivity) 5
- Stop paroxetine and continue fluoxetine 20 mg daily 5
- After stabilization on fluoxetine, it can be discontinued directly without tapering in most cases 5