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

Ontology: Baclofen (C0004609)

Definition (CHV) a drug used to treat spasm caused by back injury
Definition (CHV) a drug used to treat spasm caused by back injury
Definition (MSH) A GAMMA-AMINOBUTYRIC ACID derivative that is a specific agonist of GABA-B RECEPTORS. It is used in the treatment of MUSCLE SPASTICITY, especially that due to SPINAL CORD INJURIES. Its therapeutic effects result from actions at spinal and supraspinal sites, generally the reduction of excitatory transmission.
Definition (NCI) A synthetic chlorophenyl-butanoic acid derivative used to treat spasms due to spinal cord damage and multiple sclerosis, muscle-relaxing Baclofen acts as a gamma-aminobutyric acid (GABA) agonist specific for GABA-B receptors. It acts at spinal and supraspinal sites, reducing excitatory transmission. (NCI04)
Definition (NCI_NCI-GLOSS) A drug that is used to treat certain types of muscle spasms and is being studied in the treatment of liver cancer. Baclofen relaxes muscles by blocking certain nerve receptors in the spinal cord. It is a type of antispasmodic.
Concepts Pharmacologic Substance (T121) , Amino Acid, Peptide, or Protein (T116)
MSH D001418
SnomedCT 391810001, 387342009, 6102009
LNC LP17857-1, MTHU019852
English Baclofen, Baclophen, beta-(p-Chlorophenyl)-gamma-aminobutyric Acid, Chlorophenyl GABA, GABA, Chlorophenyl, PCP-GABA, beta-(Aminomethyl)-4-chlorobenzenepropanoic Acid, Benzenepropanoic acid, beta-(aminomethyl)-4-chloro-, 4-Amino-3-(4-chlorophenyl)-butanoic Acid, baclofen, baclofen (medication), muscle relaxants skeletal baclofen, BACLOFEN, Baclofen [Chemical/Ingredient], baclophen, Baclofen - chemical, Baclofen - chemical (substance), Baclofen (product), Baclofen (substance)
Swedish Baklofen
Czech baklofen
Finnish Baklofeeni
Russian KHLORFENIL-GAMK, BAKLOFEN, KHLORFENIL-GAMMA-AMINOMASLIANAIA KISLOTA, БАКЛОФЕН, ХЛОРФЕНИЛ-ГАМК, ХЛОРФЕНИЛ-ГАММА-АМИНОМАСЛЯНАЯ КИСЛОТА
French bêta-4-chlorophényl-GABA, PCP-GABA, Baclofène
Polish Baklofen
Japanese バクロフェン, クロロフェニルガンマアミノ酪酸
Spanish baclofeno (producto), baclofeno (sustancia), baclofeno, Baclofeno, Clorofenil GABA
German Baclofen, Baclophen, Chlorphenyl-GABA
Italian Baclofen
Portuguese Baclofeno, Clorofenil GABA

Ontology: Baclofen Infusion Implantable Pumps (C3504191)

Concepts Medical Device (T074)
English Baclofen Infusion Implantable Pumps