What are the medications for spasticity in cerebral palsy (CP)?

Medications for Spasticity in Cerebral Palsy

Botulinum toxin injections are the first-line treatment for focal spasticity in cerebral palsy, while oral medications including baclofen, tizanidine, and dantrolene are recommended for generalized spasticity. 1, 2

First-Line Medications

For Focal Spasticity

• Botulinum Toxin
  • Strongest evidence for effectiveness in CP 2
  • Recommended for localized upper limb muscles to improve range of motion, dressing, hygiene, and limb positioning 1
  • Recommended for lower limb muscles to reduce spasticity interfering with gait function 1
  • Dosing: 100-300 IU (based on predetermined diagrams for specific muscles) 1
  • Advantages: Targeted approach with fewer systemic side effects
  • Duration: Effects last 3-6 months, requiring periodic injections

For Generalized Spasticity

• Oral Baclofen

  • FDA-approved for spasticity management 3
  • Dosing: 30-80 mg/day in divided doses, titrated to effect and tolerance 1
  • Mechanism: GABA agonist that reduces muscle tone
  • Caution: May cause significant sedation, can worsen seizures in patients with epilepsy 3
  • Warning: Abrupt discontinuation can cause withdrawal symptoms including seizures and hyperthermia 4

• Tizanidine

  • FDA-approved short-acting drug for spasticity management 5
  • Particularly effective for chronic spasticity with improvements in pain 6
  • Advantage: Less muscle weakness compared to baclofen 4
  • Limitation: Short duration of effect; treatment should be reserved for times when relief is most important 5

• Dantrolene Sodium

  • Recommended for patients who need spasticity management without cognitive side effects 6, 2
  • Acts directly on skeletal muscle
  • Caution: Potential for hepatotoxicity requires liver function monitoring

Second-Line Interventions

For Severe Refractory Spasticity

• Intrathecal Baclofen
  • Indicated for severe spasticity unresponsive to maximum doses of oral medications 4
  • Delivers baclofen directly to spinal fluid at fraction of oral dose 7
  • Evidence shows >80% of patients have improvement in muscle tone 4
  • Reduces spasticity in children with CP 8, 9
  • Requires surgical implantation of pump device
  • Risks: Overdose or withdrawal symptoms if delivery system fails 4, 9

Chemical Neurolysis

• Phenol/Alcohol Injections
  • Alternative for focal spasticity management 6
  • Used when botulinum toxin is ineffective or contraindicated
  • Longer duration than botulinum toxin but potentially more side effects

Medication Selection Algorithm

1. Assess spasticity pattern:

   • Focal (affecting specific muscle groups) → Botulinum toxin
   • Generalized (affecting multiple areas) → Oral medications

2. For generalized spasticity, select based on patient characteristics:

   • Need for daytime function with minimal sedation → Tizanidine
   • Severe spasticity requiring 24-hour control → Baclofen
   • Concerns about cognitive side effects → Dantrolene
   • Patient with epilepsy → Avoid baclofen, consider dantrolene 3

3. If inadequate response to first-line treatments:

   • Consider combination therapy
   • Evaluate for intrathecal baclofen if severe, refractory spasticity

Important Considerations

• Monitor for adverse effects:

  • Sedation (especially with baclofen and tizanidine)
  • Weakness that may impair function
  • Withdrawal symptoms if medication is abruptly discontinued

• Functional goals should guide treatment:

  • Improved mobility and self-care
  • Pain reduction
  • Prevention of contractures
  • Enhanced quality of life

• Spasticity management pitfalls:

  • Overtreatment can worsen function if spasticity is being used for mobility or posture 1
  • Inadequate treatment can lead to contractures, pain, and increased care burden 1
  • Abrupt discontinuation of baclofen can cause life-threatening withdrawal 4

• Combination approach:

  • Medications should be used in conjunction with physical therapy, positioning, and orthoses 6
  • Regular range of motion exercises are essential to prevent contractures

By following this medication algorithm and considering the individual characteristics of the patient with cerebral palsy, clinicians can effectively manage spasticity while minimizing adverse effects and maximizing functional outcomes.