What are the first-line muscle relaxers for pediatric patients with muscle spasticity?

First-Line Muscle Relaxants for Pediatric Muscle Spasticity

Baclofen is the first-line muscle relaxant for treating spasticity in pediatric patients, with oral administration as the initial approach and intrathecal delivery for severe or refractory cases. 1, 2

Oral Medication Options

First-Line Treatment

• Baclofen is considered the primary oral medication for generalized spasticity in children, though safety and effectiveness have not been established in children under 12 years 3, 2
• Dosing should start low and gradually increase to minimize side effects while achieving optimal spasticity reduction 3, 4

Alternative Oral Medications

• Tizanidine may be used when baclofen is not tolerated, starting with 4mg doses and gradually increasing (2-4mg steps) to a maximum of 36mg daily, with doses repeated at 6-8 hour intervals 5, 4
• Diazepam can be effective but requires careful monitoring for respiratory depression, especially when combined with other sedative agents 6, 2
• Dantrolene sodium is the only agent acting directly on muscle tissue and may be considered when central-acting agents are ineffective 4, 2

Localized Spasticity Treatment

• Botulinum toxin A has the strongest evidence for effectiveness in treating localized spasticity in pediatric patients 2
• Phenol and alcohol injections can provide valuable transition between short-term and long-term treatments for selected muscle groups 7

Severe or Refractory Spasticity

• Intrathecal baclofen via surgically implanted pump is the most effective treatment for severe diffuse spasticity of both cerebral and spinal origin in pediatric patients 8, 2
• Careful patient assessment, selection, and continued monitoring are essential for successful intrathecal baclofen management 8

Important Considerations

• Treatment should begin at low doses and gradually increase to avoid adverse effects 4
• Baclofen should be used with caution when spasticity is utilized to sustain upright posture and balance in locomotion 3
• In patients with epilepsy, clinical state and electroencephalogram should be monitored regularly, as deterioration in seizure control has been reported with baclofen 3
• Sedation is a common side effect of muscle relaxants, and patients/caregivers should be cautioned about activities requiring alertness 3, 4

Treatment Algorithm

1. Assess spasticity severity and functional impact
2. For generalized spasticity:
   • Start with oral baclofen at low dose and titrate gradually
   • If ineffective or poorly tolerated, consider tizanidine or diazepam
   • For severe cases unresponsive to oral medications, consider intrathecal baclofen
3. For localized spasticity:
   • Consider botulinum toxin A as first-line treatment
   • Phenol or alcohol injections as alternatives for selected muscle groups
4. Regular monitoring for efficacy and side effects is essential with all treatments