Antispastic Skeletal Muscle Relaxant


Antispastic Skeletal Muscle Relaxant, Dantrolene, Dantrium

  • Pathophysiology
  1. These agents are used to reduce severe spasticity (e.g. Spinal Cord Injury, Cerebral Palsy, Multiple Sclerosis)
  • Contraindications
  1. Not indicated for general musculoskeletal problems
  • Preparations
  1. Dantrolene (Dantrium)
  2. Baclofen (Lioresal)
    1. Baclofen binds GABA B receptors
    2. Oral Baclofen does not cross blood brain barrier well
    3. Instead, Baclofen is typically used via Baclofen Intrathecal Pump (due to poor oral absorption)
    4. Taper off over 1-2 weeks (risk of Hallucinations, Seizures if abruptly stopped)
  3. Tizanidine (Zanaflex)
    1. Dose 4 mg orally every 6-8 hours (maximum 36 mg/day)
    2. Risk of hepatotoxicity and Blood Pressure changes
    3. Primarily indicated for spasticity due to Multiple Sclerosis or Spinal Cord Injury
    4. Clonidine effect (risk of Hypotension and rebound Hypertension)
    5. Taper off over 1-2 weeks (risk of Clonidine-like rebound Hypertension effect)
  • References
  1. (2019) Presc Lett 26(3):15