What are the recommendations for a 15-year-old autistic male taking Vyvanse (lisdexamfetamine) 10mg in the morning, hydroxyzine 25mg at bedtime, Zoloft (sertraline) 25mg, and clonidine 0.2mg every hour as needed, who reports decreased appetite and nocturnal eating?

Management of Appetite Suppression and Nocturnal Eating in an Adolescent on Vyvanse

The decreased appetite is a well-established adverse effect of Vyvanse (lisdexamfetamine) that requires dose timing adjustment and nutritional counseling, while the nocturnal eating pattern warrants evaluation for sleep-related eating disorder versus compensatory eating from daytime appetite suppression. 1

Understanding the Medication-Related Appetite Effects

Vyvanse is directly causing the appetite suppression. The FDA label explicitly identifies decreased appetite as one of the most common adverse reactions, occurring in 34% of pediatric patients aged 13-17 years taking lisdexamfetamine versus only 3% on placebo 1. This represents a dose-dependent effect that is consistent across all stimulant medications 2.

• Weight loss is an expected consequence, with mean losses of 0.9-2.5 pounds after just 4 weeks of therapy in pediatric patients 1
• The appetite suppression typically peaks during the medication's active duration (approximately 13 hours in children) 3
• This creates a predictable pattern where patients have minimal hunger during school/daytime hours 2

Addressing the Nocturnal Eating Pattern

The nighttime eating likely represents compensatory behavior for inadequate daytime caloric intake rather than a primary sleep disorder. When stimulant medications suppress appetite throughout the day, adolescents often experience intense hunger once the medication wears off in the evening 2.

Critical Distinction to Make:

• Sleep-related eating disorder (SRED): Patient has no memory of eating, occurs during partial arousal from sleep, often involves unusual food combinations
• Compensatory evening eating: Patient is fully conscious, eating normal foods, driven by genuine hunger from inadequate daytime intake 2

The timing of clonidine 0.2mg "q ha" (assuming this means "at bedtime" rather than "every hour") may contribute to sedation but would not typically cause SRED 2.

Immediate Management Strategy

1. Optimize Medication Timing and Nutrition

Adjust the daily eating schedule to work with, not against, the medication's pharmacokinetics:

• Ensure a substantial, high-calorie breakfast before the 10mg Vyvanse dose, as appetite will be minimal once the medication takes effect (within 1.5 hours) 3
• The medication's duration of action is approximately 13 hours 3, so appetite should return by evening
• Provide calorie-dense snacks during the late afternoon/early evening window when the medication effect is waning 2
• Avoid restricting the nighttime eating if the patient is genuinely hungry and eating appropriate foods 2

2. Monitor Growth Parameters Closely

Regular weight and height monitoring is essential in adolescents on stimulants:

• Check weight at every visit during dose optimization 2
• Plot growth curves to detect any deviation from expected trajectory 1
• The FDA label specifically warns about "long-term suppression of growth in pediatric patients" 1
• If weight loss exceeds 7% of body weight, medication adjustment is warranted 4

3. Consider Dose Reduction

At only 10mg daily, this patient is on the lowest therapeutic dose of Vyvanse 1. However, even low doses can cause significant appetite suppression in some individuals 2.

• If growth parameters are concerning or the patient is losing weight, consider reducing to 5mg or switching to a shorter-acting stimulant that allows for better appetite recovery during the day 2
• Shorter-acting formulations (immediate-release methylphenidate or amphetamine) may allow for a midday appetite window 2

4. Evaluate Medication Interactions

Review the complete medication regimen for additive appetite effects:

• Zoloft (sertraline) 25mg can cause decreased appetite and weight loss, particularly in pediatric patients 4
• In pooled pediatric trials, sertraline caused approximately 1kg more weight loss than placebo 4
• The combination of Vyvanse and Zoloft may have synergistic appetite-suppressing effects 1, 4

5. Rule Out Clonidine Dosing Error

The notation "clonidine 0.2mg q ha" requires immediate clarification:

• If this truly means "every hour," this represents a dangerous overdose (typical pediatric dosing is 0.1-0.4mg total daily) 2
• If this means "at bedtime" (hs), 0.2mg is within normal range but may contribute to morning sedation that compounds appetite issues 2
• Clonidine is appropriately used as adjunctive therapy to address stimulant-related sleep disturbances 2

Nutritional Counseling Approach

Provide specific strategies to maximize caloric intake during appetite windows:

• Front-load calories in the morning with protein-rich, calorie-dense foods (eggs, whole milk, nut butters, cheese)
• Keep portable, high-calorie snacks available for late afternoon (trail mix, protein bars, smoothies)
• Avoid low-calorie "diet" foods; prioritize nutrient and calorie density
• Consider nutritional supplements (Ensure, Boost) if solid food intake is inadequate 2

When to Escalate Care

Consult with a pediatric psychiatrist or eating disorder specialist if:

• Weight loss exceeds 7% of body weight 4
• Growth velocity declines below expected percentiles 1
• The nocturnal eating involves loss of control, binge-like episodes, or occurs during sleep without awareness
• The patient develops anxiety or preoccupation about eating/weight 1, 4

Autism-Specific Considerations

Autistic adolescents may have additional challenges with appetite and eating:

• Sensory sensitivities may limit food choices, making adequate caloric intake more difficult when appetite is suppressed
• Rigid eating patterns may not adapt well to the need for strategic meal timing
• Communication difficulties may make it harder to assess subjective hunger and satiety
• Consider involving an occupational therapist familiar with autism and feeding issues 2

Common Pitfall to Avoid

Do not simply add an appetite stimulant (such as cyproheptadine or mirtazapine) without first optimizing the timing and dosing of the causative medication. This approach treats the symptom rather than addressing the root cause and adds unnecessary medication burden 2.