What to do for an 8-year-old patient taking Vyvanse (lisdexamfetamine) 20mg for Attention Deficit Hyperactivity Disorder (ADHD) who has improved focus but is experiencing increased crying?

Management of Emotional Lability (Increased Crying) in an 8-Year-Old on Vyvanse 20mg

This child is experiencing a recognized adverse effect of stimulant medication—emotional lability or dysphoria—which requires immediate dose adjustment or medication modification rather than continuation at the current regimen. 1

Understanding the Problem

The "crying a lot" represents emotional lability, a well-documented adverse effect of stimulant medications that can manifest as tearfulness, emotional overreaction, or dysphoric mood. 1 The American Academy of Child and Adolescent Psychiatry specifically notes that children treated with stimulants can become tearful and show emotional dysregulation, particularly as medication effects fluctuate throughout the day. 1

This is NOT a contraindication to stimulant therapy, but it IS an indication that the current medication approach needs modification. 1

Immediate Management Algorithm

Step 1: Determine Timing of Symptoms

• If crying occurs primarily in late afternoon/evening (4-6 hours after dosing): This suggests "rebound" phenomenon as Vyvanse wears off, which is common with stimulants. 1
• If crying occurs throughout the day: This suggests the medication itself is causing emotional dysregulation at the current dose or formulation. 1

Step 2: Initial Intervention Based on Timing

For rebound-related crying (late day symptoms):

• Reduce the Vyvanse dose from 20mg to 10mg (the lowest available dose) to minimize the rebound effect. 2
• Monitor for 1-2 weeks to assess if lower dose maintains therapeutic benefit for ADHD while reducing emotional side effects. 2
• If 10mg provides inadequate ADHD control, consider splitting to twice-daily dosing or switching medication class entirely. 1

For all-day emotional lability:

• Immediately reduce Vyvanse to 10mg as the first-line intervention. 2
• The current 20mg dose is causing excessive emotional side effects that outweigh the therapeutic benefit. 1
• Titration should have started at lower doses (5mg methylphenidate equivalent or 2.5mg amphetamine equivalent), and this child may have been started too high. 2

Step 3: If Dose Reduction Fails (After 1-2 Week Trial)

Switch to methylphenidate-based stimulant as the next step: 2

• Methylphenidate is recommended as the traditional first-line stimulant with 70% response rates. 2
• Start with long-acting methylphenidate formulation (e.g., Concerta 18mg or equivalent) to provide consistent coverage. 2
• The American Academy of Child and Adolescent Psychiatry notes that amphetamine preparations (like Vyvanse) may cause more emotional side effects than methylphenidate in some children. 1
• Titrate methylphenidate weekly in 5-10mg increments based on response and tolerability. 2

Step 4: If Methylphenidate Also Causes Emotional Problems

Consider non-stimulant medication: 2

• Atomoxetine (Strattera) starting at 0.5 mg/kg/day, titrating to 1.2-1.4 mg/kg/day over 4-6 weeks. 2
• Atomoxetine requires 4-6 weeks for full therapeutic effect but has lower risk of emotional side effects. 2
• Extended-release guanfacine (Intuniv) 1-4mg daily is another option with effect size of ~0.7. 2

Critical Monitoring During Adjustment

At each visit (weekly during titration), systematically assess: 2

• Core ADHD symptoms using standardized rating scales from both parents and teachers. 2
• Emotional symptoms: frequency of crying, irritability, mood changes, social withdrawal. 1, 2
• Other side effects: appetite, sleep, headaches, tics. 2
• Blood pressure and pulse at every visit. 2

Common Pitfalls to Avoid

Do not continue current dose hoping symptoms will resolve: 1

• Emotional dysregulation from stimulants typically does not improve with continued exposure at the same dose. 1
• The American Academy of Child and Adolescent Psychiatry warns that clinicians should be cautious prescribing stimulants to patients with unstable mood. 1

Do not add another medication to treat the crying: 1

• The crying is a direct adverse effect of the stimulant; address the root cause first. 1

Do not assume all stimulants will cause the same problem: 1, 2

• Methylphenidate and amphetamine preparations have different side effect profiles, and switching classes is appropriate. 1, 2

Do not abandon ADHD treatment entirely: 1

• Depression and emotional symptoms can be secondary to untreated ADHD, and some patients' mood improves when ADHD is adequately treated. 1
• Systematic medication trials across different classes should be completed before concluding pharmacotherapy has failed. 2

Why Vyvanse May Be Problematic Here

Lisdexamfetamine (Vyvanse) is a prodrug that provides 12-14 hours of amphetamine effect through enzymatic conversion in the blood. 3, 4 While this long duration is advantageous for ADHD coverage, it also means prolonged exposure to amphetamine, which can increase risk of emotional side effects in vulnerable children. 1, 3 The 20mg dose may be excessive for this 8-year-old's tolerance, particularly as a starting dose. 2

Expected Timeline

• Dose reduction effects: Should see improvement in crying within 3-7 days if dose-related. 1
• Medication switch to methylphenidate: Allow 1-2 weeks at therapeutic dose to assess both efficacy and emotional tolerability. 2
• Switch to atomoxetine: Requires 4-6 weeks for full therapeutic effect. 2