Switching from Lexapro to Wellbutrin: Recommended Approach
When switching from escitalopram (Lexapro) to bupropion (Wellbutrin), taper escitalopram gradually over several weeks to months using hyperbolic dose reductions down to very low doses (potentially 1-2 mg), then initiate bupropion at 150 mg daily after completing the taper, increasing to 300 mg after 4 days if tolerated.
Tapering Escitalopram: The Critical First Step
Why Gradual Tapering Matters
Escitalopram carries significant risk for discontinuation syndrome. Studies show withdrawal symptoms occur in 56% of patients (14 of 25) who discontinue escitalopram 1. Common symptoms include dizziness (44%), muscle tension (44%), chills (44%), confusion (40%), and amnesia (28%). Higher doses and plasma concentrations substantially increase this risk 1.
Recommended Tapering Schedule
For standard-risk patients:
- Reduce dose by 25-50% every 2 weeks
- Example: 20 mg → 10 mg (2 weeks) → 5 mg (2 weeks) → 2.5 mg (2 weeks) → stop
- Total duration: 6-8 weeks 2
For higher-risk patients (longer duration of use, higher doses, previous withdrawal difficulties):
- Use hyperbolic tapering with much smaller reductions
- Taper over months, reaching doses as low as 1-2 mg before complete cessation
- This approach reduces receptor occupancy variation linearly, minimizing withdrawal 3
- May require liquid formulations or compounded "mini doses" 2, 4
Critical Pitfall to Avoid
Never use alternate-day dosing when tapering escitalopram. Despite common clinical practice, dosing every other day causes pronounced receptor occupancy fluctuations that significantly increase withdrawal risk, even at low doses 5. This approach cannot be recommended.
Evidence on Taper Duration
Research demonstrates that standard 2-4 week tapers show minimal advantage over abrupt discontinuation 3, 6. A randomized study found similar discontinuation syndrome rates with 3-day versus 14-day tapers (46% overall), with 4 patients developing emergent suicidal ideation 6. This underscores why longer, more gradual tapers are necessary for SSRIs like escitalopram.
Initiating Bupropion
Timing
Complete the escitalopram taper before starting bupropion. There is no pharmacologic reason requiring overlap, and avoiding polypharmacy during the transition simplifies symptom attribution.
Bupropion Dosing
Per FDA labeling 7:
- Start: 150 mg once daily in the morning
- After 4 days: Increase to target dose of 300 mg once daily
- Take with or without food
- Swallow whole (do not crush, divide, or chew)
Monitoring
Begin monitoring within 1-2 weeks of starting bupropion for therapeutic response and adverse effects 8. Assess for:
- Worsening depression or suicidal ideation (particularly in first 1-2 months)
- Seizure risk factors (bupropion lowers seizure threshold)
- Agitation, irritability, or unusual behavioral changes
- Sexual function improvement (bupropion has lower sexual dysfunction rates than SSRIs) 8
If inadequate response by 6-8 weeks, modify treatment 8.
Clinical Context from Guidelines
The 2023 ACP guideline found no efficacy differences between second-generation antidepressants when switching medications 9. The STAR*D trial showed similar outcomes whether switching to bupropion SR, sertraline, or venlafaxine XR in patients who didn't respond to initial SSRI therapy 9. This supports that the switch itself is reasonable, but the manner of discontinuation is what determines tolerability.
Key Takeaways
- Escitalopram withdrawal is common and dose-dependent - plan accordingly
- Hyperbolic tapering over weeks to months is superior to rapid tapers
- Avoid alternate-day dosing - it worsens withdrawal
- Complete the taper before starting bupropion at standard initiation doses
- Monitor closely in the first 2 weeks after starting bupropion for mood changes and suicidality