Transitioning from Vyvanse 50 mg to Quillivant XR
You should discontinue Vyvanse and initiate Quillivant XR at 20 mg once daily in the morning, then titrate weekly by 10-20 mg increments based on response and tolerability, rather than attempting a direct milligram-per-milligram conversion. 1
Rationale for Non-Equivalent Dosing
Do not substitute methylphenidate products for amphetamine products on a milligram-per-milligram basis because these medications have fundamentally different pharmacokinetic profiles, base compositions, and mechanisms of action 1. Lisdexamfetamine (Vyvanse) is an amphetamine prodrug, while Quillivant XR is an extended-release methylphenidate formulation—these are distinct stimulant classes requiring independent titration 2.
Specific Transition Protocol
Step 1: Discontinuation and Initiation
- Stop Vyvanse completely on the day you plan to start Quillivant XR 1
- Begin Quillivant XR at 20 mg once daily in the morning, regardless of the previous Vyvanse dose 1
- This starting dose applies to patients 6 years and older 1
Step 2: Titration Schedule
- Titrate weekly in increments of 10-20 mg based on symptom control and adverse effects 1
- Stimulant medications can be effectively titrated on a 7-day basis, though urgent situations may allow titration as quickly as every 3 days 2
- Maximum recommended dose is 60 mg daily; doses above this have not been studied 1
Step 3: Administration Requirements
- Vigorously shake the bottle for at least 10 seconds before each dose to ensure proper suspension 1
- Administer once daily in the morning with or without food 1
- Use only the oral dosing dispenser provided with the product 1
Expected Response and Monitoring
More than 70% of children and adolescents with ADHD respond to methylphenidate when a full range of doses is administered 2. If you trial both methylphenidate and amphetamine classes at adequate doses, more than 90% of patients will have a beneficial response to one of these stimulant classes 2.
Key monitoring points:
- Symptom response is typically seen rapidly with stimulants, allowing relatively quick titration 2
- Assess for common adverse effects including decreased appetite (62.4%), insomnia (28.7%), irritability/aggression (26.1%), weight decrease (21.1%), and mood swings (13.9%) 3
- Monitor blood pressure, heart rate, and growth parameters regularly 1
Important Clinical Considerations
Why This Switch May Be Necessary
The most frequent reasons for switching between stimulants are adverse effects (70%) and lack of efficacy (52%) 3. If Vyvanse was discontinued due to adverse effects, be aware that methylphenidate and amphetamines have similar adverse effect profiles, though most adverse effects may be less frequent after switching 3.
Realistic Expectations
Among children switching to lisdexamfetamine from methylphenidate, only 41.3% continued treatment for a year or longer 3. The most common reasons for discontinuation of any stimulant remain adverse effects (74.4%) and lack of efficacy (34.7%) 3.
Contraindications and Precautions
- Do not use if the patient is taking MAOIs or within 14 days of MAOI discontinuation due to risk of hypertensive crisis 1
- Screen for cardiac disease with careful history, family history of sudden death, and physical examination before initiating 1
- Assess for motor/verbal tics or Tourette's syndrome before starting 1
- Avoid alcohol while taking Quillivant XR 1
Common Pitfalls to Avoid
- Do not attempt dose equivalency calculations between amphetamine and methylphenidate products—this is explicitly contraindicated 1
- Do not skip the vigorous shaking step—failure to shake for at least 10 seconds will result in inaccurate dosing 1
- Do not assume immediate therapeutic effect at starting dose—titration over several weeks may be necessary to achieve optimal symptom control 2, 1
- Do not overlook the abuse potential—both medications are Schedule II controlled substances requiring secure storage and monitoring for signs of misuse 1