What is the best strategy to switch from Strattera (atomoxetine) 80mg to Qelbree (viloxazine) 200mg?

Switching from Strattera 80mg to Qelbree 200mg

The recommended strategy is to perform a 5-day washout of atomoxetine (Strattera) before initiating viloxazine ER (Qelbree) at 200mg once daily, with flexible titration up to 600mg daily based on response and tolerability over subsequent weeks. 1

Evidence-Based Switching Protocol

Washout Period

• Discontinue atomoxetine for 5 days before starting viloxazine ER 1
• Atomoxetine can be discontinued abruptly without rebound effects or discontinuation syndrome 2
• This washout period was successfully used in a comparative study of 50 patients switching from atomoxetine to viloxazine ER 1

Initial Viloxazine ER Dosing

• Start viloxazine ER at 200mg once daily after the washout period 3
• This is the FDA-approved starting dose for adults 3
• The 200mg starting dose can be taken as a single daily dose 3

Titration Strategy

• Increase by 200mg increments at weekly intervals based on response and tolerability 3
• Maximum daily dose is 600mg 3
• In clinical practice, mean effective doses were 300mg (range 100-600mg once daily) 1

Expected Timeline and Response

Onset of Action

• 86% of patients reported positive response by 2 weeks on viloxazine ER versus only 14% on atomoxetine 1
• This represents a significantly faster onset compared to atomoxetine's typical 6-12 weeks to full therapeutic effect 4, 5

Efficacy Improvements

• Patients switching from atomoxetine to viloxazine ER demonstrated significantly greater improvements in both inattention and hyperactivity/impulsivity symptoms 1
• In pediatric patients, ADHD-RS-5 scores improved from 33.1 on atomoxetine to 13.9 on viloxazine ER 1
• In adult patients, AISRS scores improved from 28.8 on atomoxetine to 11.9 on viloxazine ER 1

Tolerability Considerations

Side Effect Profile

• Viloxazine ER has superior tolerability compared to atomoxetine 1
• Only 4% discontinued viloxazine ER due to side effects (fatigue) versus 36% who discontinued atomoxetine 1
• Common atomoxetine side effects that led to discontinuation included GI upset, irritability, fatigue, and insomnia 1
• Viloxazine ER has minimal effects on appetite, growth, and sleep compared to stimulants 6

Patient Preference

• 96% of patients preferred viloxazine ER over atomoxetine in a comparative study 1
• 85% of patients on concomitant stimulants chose to taper them after stabilizing on viloxazine ER 1

Monitoring During the Switch

Assessment Points

• Evaluate response at 2 weeks given the rapid onset of viloxazine ER 1
• Continue monitoring through 4 weeks for full assessment of efficacy and tolerability 1
• Monitor blood pressure and heart rate during titration 5

Dose Adjustments

• If inadequate response at 200mg after 1 week, increase to 400mg 3
• Further increases to 600mg can be made at weekly intervals if needed 3
• If side effects occur, consider maintaining current dose or reducing by 200mg 3

Important Clinical Pearls

Pharmacological Differences

• Viloxazine ER is a selective norepinephrine reuptake inhibitor with serotonin modulating activity, distinct from atomoxetine's pure NRI mechanism 6, 7
• Unlike atomoxetine, viloxazine has minimal elevation of dopamine in the nucleus accumbens, reducing abuse potential 6
• Viloxazine ER provides consistent 24-hour coverage with once-daily dosing 7, 8

Contraindications and Cautions

• There is no published safety data for viloxazine in pregnancy or breastfeeding 3
• Limited data exists on efficacy and tolerability in adults, though recent approval expands this evidence base 3, 8
• Alternative agents may be preferred in pregnancy or breastfeeding contexts 3

No Cross-Tapering Required

• Unlike switching between some psychotropics, direct switch after washout is the established protocol rather than cross-tapering 1
• This simplifies the switching process and reduces polypharmacy exposure 1