Barbiturate Toxicity

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Barbiturates are a class of sedative-hypnotic drugs. They are commonly used as antiepileptics (phenobarbital) and for the induction of general anesthesia (thiopental). Some states administer barbiturates for physician-assisted suicide/euthanasia and use them for capital punishment by lethal injection. Their use in clinical practice has largely been replaced by benzodiazepines such as alprazolam, diazepam, and lorazepam due to the lower risk of overdose and available antidote to reverse toxicity. Barbiturates are used as a laboratory buffer and can be found in clinical and research laboratories.[1][2]

Barbiturates are controlled substances that pose a high risk for abuse, given their psychoactive effects. Restrictions on access to barbiturates have caused the number of overdoses to decline. Common barbiturates include the following:

  • Methohexital and thiopental are used as anesthetics
  • Phenobarbital and primidone are used in the treatment of seizures
  • Amobarbital is used as an investigative agent in the Wada test (neurological assessment of cerebral hemispheres)
  • Butalbital, in combination with other medications, is used for headaches and muscle pain