What is the recommended protocol for switching an adult patient from escitalopram (Lexapro) 20 mg daily to bupropion (Wellbutrin)?

Switching from Lexapro 20mg to Wellbutrin: Recommended Protocol

When switching from escitalopram (Lexapro) 20 mg to bupropion (Wellbutrin), perform a gradual taper of escitalopram over 10-14 days followed by a washout period before initiating bupropion at 150 mg daily, then titrate to 150 mg twice daily after 3-7 days. This conservative approach minimizes withdrawal symptoms from the SSRI and allows for safe initiation of bupropion 1.

Step-by-Step Switching Protocol

Week 1-2: Taper Escitalopram

• Reduce escitalopram from 20 mg to 10 mg daily for 7 days
• Then reduce to 5 mg daily for another 7 days
• The FDA label explicitly recommends gradual dose reduction rather than abrupt cessation to limit withdrawal symptoms 1

Week 2-3: Washout Period (Optional but Safer)

• After completing the taper, consider a 3-7 day washout period with no antidepressant
• This conservative approach reduces risk of drug interactions and allows monitoring for withdrawal symptoms versus depression relapse 2
• If the patient cannot tolerate a medication-free period due to severe symptoms, you may proceed directly to bupropion initiation after completing the taper

Week 3+: Initiate Bupropion

• Start bupropion 150 mg once daily in the morning 3
• After 3-7 days, increase to 150 mg twice daily (maximum 300 mg/day)
• Give the second dose before 3 PM to minimize insomnia risk 3
• The activating properties of bupropion make morning dosing essential

Critical Safety Considerations

Contraindications to Bupropion

Do not use bupropion in patients with:

• Seizure disorders or conditions that lower seizure threshold (stroke, brain metastases, eating disorders) 4
• Current use of MAO inhibitors or within 14 days of discontinuation 5
• Uncontrolled hypertension 5
• Closed-angle glaucoma 4

Monitor for Neuropsychiatric Effects

• Both medications carry black box warnings for suicidal thoughts and behaviors, particularly in patients under 24 years 1
• Closely monitor during the switch period for worsening depression, agitation, or emergence of suicidal ideation 4, 5
• While uncommon, these effects require immediate discontinuation if they occur

Withdrawal Symptoms vs. Relapse

Key distinction: Withdrawal symptoms from escitalopram typically emerge within 1-5 days of dose reduction and include:

• Dizziness, paresthesias, headache
• Flu-like symptoms, insomnia
• Irritability, anxiety

If intolerable withdrawal symptoms occur, resume the previous escitalopram dose and taper more gradually 1, 2.

Depression relapse typically occurs later (weeks) and presents as return of core depressive symptoms (anhedonia, hopelessness, sleep/appetite changes).

Clinical Context for This Switch

When This Switch Makes Sense

Bupropion is particularly appropriate when switching from escitalopram for:

• Sexual dysfunction (bupropion has significantly lower rates than SSRIs) 6
• Weight gain or metabolic concerns (bupropion may promote weight loss)
• Fatigue or apathy (bupropion's activating properties can improve energy) 3
• Comorbid smoking cessation needs 4, 5
• Depression with comorbid ADHD symptoms (dopaminergic effects)

When to Reconsider This Switch

Avoid or use extreme caution with bupropion in patients with:

• Prominent anxiety symptoms - Bupropion's activating properties can worsen anxiety, particularly at higher doses 7. While some data suggest comparable anxiolytic effects to SSRIs in mild-moderate anxiety, SSRIs remain preferable for severe anxiety 7
• Insomnia - The stimulating effects can exacerbate sleep problems
• Agitation - Should not be used in agitated patients 3

Expected Timeline and Outcomes

Response Expectations

• After switching antidepressants, approximately 25% of patients achieve remission 8
• Bupropion may show rapid improvement in energy levels within 1-2 weeks 3
• Full therapeutic trial requires 4-8 weeks at target dose 3
• Research shows no significant difference in efficacy between switching to bupropion versus other antidepressants like sertraline or venlafaxine 8

Follow-Up Schedule

• Week 1-2 (during taper): Weekly contact to monitor withdrawal symptoms
• Week 3-4 (bupropion initiation): Weekly visits to assess tolerability and titrate dose
• Weeks 4-12: Every 2-4 weeks to monitor response and side effects
• If no response by 12 weeks: Consider alternative strategy 3

Alternative Approach: Direct Cross-Taper

In select cases where the patient cannot tolerate a medication-free period, a direct cross-taper may be considered 2, 9:

• Start bupropion 150 mg daily while maintaining escitalopram 20 mg
• After 3-7 days, reduce escitalopram to 10 mg while increasing bupropion to 150 mg twice daily
• After another week, reduce escitalopram to 5 mg for one week
• Then discontinue escitalopram

This approach carries higher risk and requires closer monitoring, but avoids a treatment gap. The pharmacologic profiles of escitalopram (SSRI) and bupropion (NDRI) are sufficiently different that direct switching is generally well-tolerated 2, 9, unlike switches involving MAOIs or certain tricyclics.

Common Pitfalls to Avoid

1. Abrupt discontinuation of escitalopram - Always taper to minimize withdrawal syndrome 1, 2
2. Starting bupropion at full dose - Begin at 150 mg daily to assess tolerability
3. Evening dosing of bupropion - Causes insomnia; second dose must be before 3 PM 3
4. Inadequate monitoring period - The switch period is high-risk for both withdrawal and worsening depression
5. Ignoring seizure risk factors - Carefully screen history before prescribing bupropion