Movement Disorders in Pediatrics: Pharmacological Management
Key Concepts
- Movement disorders in children require careful evaluation before initiating pharmacotherapy
- Drug selection depends on the specific movement disorder type, severity, and impact on daily activities
- Regular monitoring for side effects and dose adjustments is crucial in pediatric populations
- Treatment often requires a multi-modal approach including physical therapy and occupational therapy
Clinical Assessment Points
- Accurate classification of movement disorder type
- Evaluation of severity and functional impact
- Assessment of comorbid conditions
- Consideration of age-appropriate interventions
Antispasticity Agents
Baclofen
Mechanism
- GABA-B receptor agonist
- Reduces muscle tone by decreasing excitatory neurotransmitter release
Dosing
- Initial: 2.5-5 mg TID
- Maximum: 20-40 mg/day in children 2-7 years
- 60-80 mg/day in children >8 years
Side Effects
- Sedation
- Weakness
- Dizziness
- Confusion
Dantrolene
Mechanism
- Direct muscle relaxant
- Inhibits calcium release from sarcoplasmic reticulum
Dosing
- Initial: 0.5 mg/kg twice daily
- Maximum: 3 mg/kg/dose (max 100 mg/dose) QID
Monitoring
- Liver function tests monthly for first 3 months
- Then every 3 months for first year
Dystonia Management
Trihexyphenidyl
Clinical Use
- First-line for primary dystonia
- Particularly effective in children with generalized dystonia
Dosing
- Starting: 0.5-1 mg daily
- Increase gradually over weeks
- Typical maintenance: 0.5-3 mg/kg/day divided TID
Botulinum Toxin
Indications
- Focal dystonia
- Cervical dystonia
- Limb dystonia
Administration
- Dose based on muscle size and severity
- Effects last 3-6 months
- Regular reassessment needed
Parkinsonian Symptoms
Levodopa/Carbidopa
Indications
- Dopa-responsive dystonia
- Juvenile parkinsonism
Dosing Strategy
- Start: 1 mg/kg/day of levodopa
- Increase weekly
- Divide into 3-4 doses daily
Monitoring
- Response within days for dopa-responsive dystonia
- Watch for motor fluctuations
- Monitor for psychiatric side effects
Chorea Treatment
Tetrabenazine
Mechanism
- VMAT2 inhibitor
- Depletes presynaptic dopamine
Dosing
- Initial: 12.5 mg daily
- Titrate weekly
- Maximum: 200 mg/day divided TID
Side Effects
- Depression
- Parkinsonism
- Sedation
Tic Disorders
Alpha-2 Agonists
Clonidine
- Starting dose: 0.05 mg at bedtime
- Maximum: 0.2-0.3 mg/day divided TID-QID
- Monitor blood pressure
Antipsychotics
Risperidone
- Start: 0.25 mg daily
- Typical range: 0.5-3 mg/day
- Monitor metabolic parameters
Further Reading
