Pentobarbital

Pentobarbital

Clinical data
Trade names	Nembutal
AHFS/Drugs.com	Monograph
MedlinePlus	a682416
License data	US FDA: Pentobarbital
Pregnancy category	AU: C US: D (Evidence of risk)
Routes of administration	By mouth, IV, IM, rectal; also intraperitoneal & intracardiac (for animal euthanasia)
ATC code	N05CA01 (WHO) QN51AA01 (WHO)
Legal status
Legal status	AU: S8 (Controlled) CA: Schedule IV DE: Anlage III (Prescription only) UK: Class B US: Schedule II UN: Psychotropic Schedule III In general: ℞ (Prescription only)
Pharmacokinetic data
Bioavailability	70–90% (oral); 90% (rectal)
Protein binding	20–45%
Metabolism	Liver
Biological half-life	15–48 hours
Excretion	Kidney
Identifiers
IUPAC name 5-Ethyl-5-(1-methylbutyl)-2,4,6(1H,3H,5H)-pyrimidinetrione
CAS Number	76-74-4 Y
PubChem CID	4737
IUPHAR/BPS	5480
DrugBank	DB00312 Y
ChemSpider	4575 Y
UNII	I4744080IR
KEGG	D00499 Y
ChEBI	CHEBI:7983 Y
ChEMBL	CHEMBL448 Y
ECHA InfoCard	100.000.895
Chemical and physical data
Formula	C11H18N2O3
Molar mass	226.27
3D model (Jmol)	Interactive image
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

Pentobarbital (US English) or pentobarbitone (UK English) is a short-acting barbiturate. Pentobarbital can occur as both a free acid and as salts of elements such as sodium and calcium. The free acid is only slightly soluble in water and ethanol.

One brand name for this drug is Nembutal, coined by 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). Nembutal is trademarked and manufactured by the Danish pharmaceutical company Lundbeck, and is the only injectable form of pentobarbital approved for sale in the United States.

In high doses, pentobarbital causes death by respiratory arrest. In the United States, the drug has been used for executions of convicted criminals. Lundbeck (one of many manufacturers) does not permit its sale to prisons or corrections departments to carry out the death penalty.

Typical applications for pentobarbital are sedative, hypnotic for short term, preanesthetic and control of convulsions in emergencies.

It is also used as a veterinary anesthetic agent.

Pentobarbital also has an application in reducing intracranial pressure in Reye's syndrome, traumatic brain injury and induction of coma in cerebral ischemia patients. Pentobarbital-induced coma has been advocated in patients with acute liver failure refractory to mannitol.

Pentobarbital can induce death when used in high doses. It is used for euthanasia for humans as well as nonhumans. It is also used by itself, or in combination with complementary agents such as phenytoin, in commercial animal euthanasia injectable solutions.