Significations et usages de Pentobarbital

Pentobarbital

Systematic (IUPAC) name
5-Ethyl-5-(1-methylbutyl)-2,4,6(1H,3H,5H)-pyrimidinetrione
Clinical data
AHFS/Drugs.com	monograph
MedlinePlus	a682416
Pregnancy cat.	D (USA)
Legal status	USA: Schedule II (oral and parenteral); Schedule III (rectal), UK: Class B Controlled Substance
Routes	Oral, Intravenous, Intramuscular, Rectal; also Intraperitoneal & Intracardiac (for animal euthanasia)
Pharmacokinetic data
Bioavailability	70-90% oral; 90% rectal
Protein binding	20-45%
Metabolism	Hepatic
Half-life	15-48 hours
Excretion	Renal
Identifiers
CAS number	76-74-4 Y
ATC code	N05CA01 QN51AA01
PubChem	CID 4737
DrugBank	DB00312
ChemSpider	4575 Y
UNII	I4744080IR Y
KEGG	D00499 Y
ChEBI	CHEBI:7983 Y
ChEMBL	CHEMBL448 Y
Chemical data
Formula	C11H18N2O3
Mol. mass	226.27
SMILES O=C1NC(=O)NC(=O)C1(C(C)CCC)CC
InChI InChI=1S/C11H18N2O3/c1-4-6-7(3)11(5-2)8(14)12-10(16)13-9(11)15/h7H,4-6H2,1-3H3,(H2,12,13,14,15,16) Y Key:WEXRUCMBJFQVBZ-UHFFFAOYSA-N Y
Y (what is this?)  (verify)

Pentobarbital is a short-acting barbiturate that was first synthesized in 1928. Pentobarbital is available as both a free acid and a sodium salt, the former of which is only slightly soluble in water and ethanol.^[1] One brand name for this drug is Nembutal, coined by Dr. John S. Lundy, who started using it in 1930, from the structural formula of the sodium salt—Na (sodium) + ethyl + methyl + butyl + al (common suffix for barbiturates).^[2]

  Uses

  Approved

Pentobarbital's FDA-approved human uses include treatment of seizures and preoperative (and other) sedation; it is also approved as a short-term hypnotic.^[3]

  Unapproved / investigational / off-label

Off-label uses of pentobarbital include reduction of intracranial pressure in Reye's syndrome, traumatic brain injury and induction of coma in cerebral ischemia patients.^[3] Pentobarbital-induced coma has been advocated in patients with acute liver failure refractory to mannitol.^[4]

  Veterinary medicine

In veterinary medicine, sodium pentobarbital is used as an anaesthetic. It is also used by itself, or in combination with complementary agents such as phenytoin, in commercial animal euthanasia injectable solutions. ^[5]

  Human euthanasia

In the Netherlands, the standard protocol for physician-assisted euthanasia is intravenously induced thiopental anesthesia, followed by alcuronium bromide- or pancuronium bromide-induced respiratory collapse. If the patient wishes to take the euthanasiant himself/herself, the standard protocol is a concentrated oral solution of 100 ml mixtura nontherapeutica pentobarbitali containing 9 grams of pentobarbital sodium along with sugar syrup in a 20% ethanol solution.^[6] (Dutch)

Pentobarbital has also been used for physician-assisted suicide. In the US state of Oregon, "oral doses of a barbiturate" have been used for this purpose.^[7]

In Switzerland, the only country that allows foreigners to have assisted suicide, the Dignitas clinic uses the antiemetic drug metoclopramide followed by sodium pentobarbital for the procedure.^[8] It was used in the Northern Territory of Australia during the brief period in which euthanasia was permitted.^{[citation needed]}

  Capital punishment

The US state of Texas executed its first death row inmate with a single lethal injection of the sedative pentobarbital on July 18, 2012. Yokamon Hearn, 33, was convicted for the carjacking and murder of a Dallas stockbroker in 1998.^[9] The sole use of Pentobarital in U.S is set to become more widespread after several states, including Ohio, Arizona, Idaho and Washington made the decision to switch following shortages of the Pancuronium bromide, a muscle relaxant previously used as one component in a 3-drug cocktail.^[10]

The Danish manufacturer of pentobarbital, Lundbeck, expressed displeasure at this use of their product, and on July 1, 2011, announced they would block sales of the drug to U.S. prisons that carry out the death penalty.

Lundbeck adamantly opposes the distressing misuse of our product in capital punishment.^[11]

They explained this decision with their commitment to UN human rights principles. ^[12]

  Metabolism

Pentobarbital undergoes first-pass metabolism in the liver and possibly the intestines.^[13]

  Drug interactions

Administration of alcohol, opioids, antihistamines, other sedative-hypnotics, and other central nervous system depressants will cause possible additive effects.^[3]

  Recreational use

Pentobarbital is a drug that has been used recreationally.^[14]

  Chemistry

Pentobarbital is synthesized by methods analogous to that of amobarbital, the only difference being that the alkylation of α-ethylmalonic ester is carried out with 2-bromopentane (not 1-bromo-3-methylbutane) to give pentobarbital.^[15][16][17]

  References

  External links

• Barbiturates on Erowid