Clinical presentation

If ingested in large amounts, baclofen can cause severe effects and, after massive ingestions, the presentation can mimic brain death. Effects of baclofen poisoning include:

• central nervous system (CNS) effects
  • altered conscious state, respiratory depression, coma
  • myoclonus and seizures—early presentation due to reduced presynaptic GABA release; late presentation due to baclofen withdrawal
  • baclofen-associated delirium—can develop following resolution of coma, and may last 1 to 3 days
  • hypotonia, hyporeflexia, mydriasis, hypothermia
  • loss of brainstem reflexes that can mimic brain death—can occur with severe toxicity and last 24 to 48 hours
• cardiovascular toxicity
  • bradycardia, tachycardia, hypertension
  • hypotension (less common)
• baclofen-induced morbilliform rash (rare).