What is the appropriate protocol for switching an adult with ADHD from Adderall (amphetamine/dextroamphetamine) 10 mg to Vyvanse (lisdexamfetamine), including initial dosing, titration, monitoring, and contraindications?

Switching from Adderall 10mg to Vyvanse in Adults with ADHD

Start Vyvanse at 30 mg once daily in the morning, which is the FDA-approved initial dose for adults with ADHD, regardless of prior Adderall dose. 1

Initial Dosing Protocol

When switching from Adderall 10 mg to Vyvanse (lisdexamfetamine), you should:

• Discontinue Adderall and start Vyvanse at 30 mg once daily the following morning 1
• There is no direct dose conversion formula between these medications—Vyvanse requires independent titration
• Take Vyvanse in the morning with or without food; avoid afternoon dosing due to insomnia risk 1
• The medication can be swallowed whole as a capsule, or the capsule can be opened and mixed with yogurt, water, or orange juice if needed 1

The 30 mg starting dose applies universally to adults initiating Vyvanse, even those previously on stimulants. Research specifically examining adults switching from amphetamine products (including Adderall) to Vyvanse demonstrated that starting at 30 mg and titrating upward was effective, even in patients who remained symptomatic on their prior amphetamine therapy 2.

Titration Schedule

Increase the dose in increments of 10-20 mg at approximately weekly intervals based on symptom control and tolerability 1:

• Week 1: 30 mg daily
• Week 2: 40-50 mg daily (if needed)
• Week 3: 50-60 mg daily (if needed)
• Week 4+: Up to maximum of 70 mg daily (if needed)

The maximum FDA-approved dose is 70 mg once daily 1. Clinical guidelines for amphetamine products suggest weekly dose adjustments of 5-10 mg increments 3, but Vyvanse's FDA label specifically recommends 10-20 mg increments given its prodrug formulation and longer duration of action.

Monitoring Requirements

Initial Titration Phase (Weeks 1-4)

Obtain baseline measurements before starting Vyvanse 3:

• Blood pressure and pulse
• Height and weight
• Cardiac history (personal and family history of sudden death, ventricular arrhythmia, structural cardiac disease)
• History of motor/verbal tics or Tourette's syndrome
• Substance abuse history

During titration, assess weekly 3:

• ADHD symptom severity using standardized rating scales (ADHD-RS-IV or similar)
• Specific side effects: insomnia, appetite suppression, headaches, anxiety, cardiovascular symptoms, tics
• Blood pressure and pulse at each visit or via phone contact
• Weight at each visit

Maintenance Phase (After Dose Stabilization)

• Monthly visits initially until symptoms stabilize 3
• Quarterly blood pressure and pulse checks 3
• Annual height and weight monitoring
• More frequent monitoring if side effects emerge or comorbid psychiatric conditions exist

Contraindications

Absolute contraindications 3:

• Previous hypersensitivity to lisdexamfetamine or amphetamine products
• Current or recent (within 14 days) monoamine oxidase inhibitor use
• Active psychotic disorder
• Symptomatic cardiovascular disease
• Glaucoma
• Hyperthyroidism
• Uncontrolled hypertension
• History of stimulant abuse (unless in controlled/supervised setting)

Relative contraindications requiring careful consideration 3:

• Seizure disorder (ensure controlled on anticonvulsants before initiating)
• Anxiety disorders (though package insert warnings may be overstated based on recent literature)
• Motor tics or Tourette's syndrome (though recent evidence suggests these may not worsen with treatment)

Important Clinical Considerations

Why Not Use Direct Dose Conversion?

Unlike switching between methylphenidate formulations, there is no established conversion ratio between Adderall and Vyvanse. Vyvanse is a prodrug that requires enzymatic conversion in red blood cells to become active d-amphetamine 4, resulting in different pharmacokinetics than immediate-release mixed amphetamine salts. The 30 mg starting dose allows assessment of individual response to this unique delivery system.

Expected Response Timeline

Vyvanse demonstrates efficacy within the first week of treatment at adequate doses 1. The medication provides approximately 12-14 hours of symptom control 4, which is longer than the 10 mg twice-daily Adderall regimen the patient was likely using. This extended duration may provide better all-day coverage without requiring multiple doses.

Switching Due to Inadequate Response

Research shows that 41% of medication-naive adults require switching between stimulant families (methylphenidate vs. amphetamine) due to poor tolerability 5. However, since this patient is already on an amphetamine product (Adderall), switching to Vyvanse (another amphetamine) may provide better tolerability through its smoother pharmacokinetic profile while maintaining the same medication class.

Managing Side Effects

If dose-limiting adverse events occur during titration:

• Reduce to the previous well-tolerated dose
• Consider slower titration intervals (every 2 weeks instead of weekly)
• Assess timing of administration (ensure morning dosing to minimize insomnia)
• Monitor for appetite suppression and weight loss—weigh at each visit 3

Renal Impairment Adjustments

If the patient has renal impairment 1:

• Severe (GFR 15-30): Maximum dose 50 mg daily
• End-stage renal disease (GFR <15): Maximum dose 30 mg daily

Risk of Tolerance

Be aware that 2.7-24.7% of patients may develop tolerance to stimulants over time 6. If previously effective doses lose efficacy, consider drug holidays, switching formulations, or clinical reassessment rather than automatically increasing doses beyond the therapeutic range.