A patient currently taking 50 mg lisdexamfetamine (Vyvanse) wishes to switch to methylphenidate (Concerta); what initial Concerta dose should be started?

Switching from Vyvanse 50 mg to Concerta: Recommended Starting Dose

Start your patient on Concerta 36 mg once daily in the morning. 1, 2

Rationale for 36 mg Starting Dose

The FDA-approved conversion table for patients currently on methylphenidate provides clear guidance that can be extrapolated to amphetamine-based stimulants. For patients switching from another stimulant at moderate therapeutic doses, Concerta 36 mg represents the appropriate starting point rather than the lowest 18 mg dose, which is reserved for stimulant-naïve patients. 2

Your patient's current Vyvanse 50 mg dose sits in the mid-to-upper therapeutic range (typical range 30-70 mg daily), indicating she requires substantial dopaminergic coverage throughout the day. 1 The 36 mg Concerta dose provides methylphenidate exposure roughly equivalent to 10 mg immediate-release methylphenidate three times daily (30 mg total daily dose), which represents a reasonable cross-conversion from her current amphetamine regimen. 1, 2

Why Not Start at 18 mg?

The 18 mg starting dose is explicitly designated for patients who are stimulant-naïve or not currently taking methylphenidate. 2 Starting at this low dose in a patient already tolerating Vyvanse 50 mg would likely result in inadequate symptom control and unnecessary treatment disruption. The FDA label specifically distinguishes between new patients (18 mg start) and those already on stimulants, for whom higher initial doses are appropriate based on clinical judgment. 2

Implementation Protocol

Week 1: Initial Switch

• Discontinue Vyvanse immediately and start Concerta 36 mg the next morning—no washout period is required when switching between stimulant classes. 1
• Administer once daily in the morning with or without food. 2
• The tablet must be swallowed whole; it cannot be chewed, crushed, or divided due to its osmotic-pump delivery system. 2

Weeks 2-4: Titration Phase

• If symptom control is inadequate after one week at 36 mg, increase to 54 mg once daily. 1, 2
• Doses may be increased in 18 mg increments at weekly intervals for patients who have not achieved optimal response. 2
• The maximum recommended adult dose is 72 mg daily; doses above this have not been studied and are not recommended. 2

Monitoring Parameters

• Measure blood pressure and pulse at baseline (before the switch) and at each dose adjustment, as both Vyvanse and Concerta can elevate cardiovascular parameters. 1, 3
• Assess ADHD symptom control using standardized rating scales at weeks 1,2, and 4. 1
• Monitor for common adverse effects including decreased appetite, insomnia, headache, and irritability. 1, 4
• Track sleep quality and timing, as Concerta's 12-hour duration may differ from Vyvanse's 13-14 hour coverage. 1

Expected Outcomes and Adjustments

Approximately 70-80% of patients achieve good symptom control when methylphenidate is properly titrated, though individual response varies. 1, 3 If your patient does not achieve adequate response after reaching 54-72 mg daily for 2-4 weeks, consider that roughly 40% of patients respond preferentially to one stimulant class over another. 1, 3 In such cases, returning to an amphetamine-based long-acting formulation may be warranted.

Key Differences to Discuss with Your Patient

Concerta provides approximately 12 hours of symptom coverage through its OROS osmotic-pump system, which produces an ascending plasma concentration pattern throughout the day. 5, 1 This differs from Vyvanse's prodrug mechanism, which typically provides 13-14 hours of coverage with a different pharmacokinetic profile. 1 Some patients notice Concerta's effects taper earlier in the evening compared to Vyvanse.

The adverse effect profiles are similar but not identical. 4 Post-hoc analyses comparing lisdexamfetamine and OROS-methylphenidate show that amphetamines (like Vyvanse) tend to cause more appetite suppression, weight loss, and insomnia, while methylphenidate formulations like Concerta are associated with slightly more headache and nasopharyngitis. 4

Common Pitfalls to Avoid

• Do not start at 18 mg in a patient already on Vyvanse 50 mg—this represents significant under-dosing and will likely result in breakthrough symptoms. 1, 2
• Do not assume the first dose will be optimal—systematic titration is essential, with most adults requiring 36-54 mg for adequate control. 1, 2
• Do not crush or split the tablet to adjust dosing, as this destroys the extended-release mechanism; use the available strengths (18,27,36,54 mg) instead. 2
• Do not delay titration unnecessarily—if symptoms remain inadequately controlled after one week, increase the dose rather than waiting longer. 1, 2