III. Pharmacology

  1. Baclofen is a Skeletal Muscle Relaxant that binds GABA B receptors
    1. Baclofen hyperpolarizes afferent nerve fibers
      1. Blocks presynaptic Calcium influx
      2. Blocks presynaptic Potassium efflux
    2. Inhibits spinal cord reflexes
    3. Reduces Muscle spasticity
  2. Oral Baclofen does not cross blood brain barrier well
    1. Requires intolerable oral doses to offer effect
  3. Instead, Baclofen is typically used via Baclofen Intrathecal Pump
    1. Intrathecal Baclofen has fewer side effects and may be used at low dose

IV. Dosing

  1. Baclofen 50-100 mcg/day via Intrathecal Pump (up to 900 mcg) and slowly titrate to effect
  2. Small dose modifications can have significant effects on patient findings (due to direct CSF drug delivery)
  3. Taper off over 1-2 weeks (risk of Hallucinations, Seizures if abruptly stopped)
    1. See Baclofen Withdrawal

VI. References

  1. Riley and LoVecchio (2021) Crit Dec Emerg Med 35(5):28

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Related Studies

Cost: Medications

baclofen (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
BACLOFEN 10 MG TABLET Generic $0.05 each
BACLOFEN 20 MG TABLET Generic $0.09 each
BACLOFEN 5 MG TABLET Generic $0.26 each
BACLOFEN 5 MG/5 ML SOLUTION Generic $1.06 per ml