Pentobarbital

From Wikipedia, the free encyclopedia

Pentobarbital chemical structure
Pentobarbital
Systematic (IUPAC) name
5-Ethyl-5-(1-methylbutyl)-
2,4,6(1
H,3H,5H)-pyrimidinetrione
Identifiers
CAS number 76-74-4
ATC code N05CA01
PubChem 4737
DrugBank APRD01174
Chemical data
Formula C11H17N2O3 
Mol. weight 226.1317
Pharmacokinetic data
Bioavailability  ?
Metabolism Hepatic
Half life 15-48 hours
Excretion Renal
Therapeutic considerations
Pregnancy cat.

D (USA)

Legal status

USA: Schedule II (oral and parenteral); Schedule III (rectal)

Routes Oral, Intravenous, Intramuscular, Rectal; also Intraperitoneal & Intracardiac (for animal euthanasia)

Pentobarbital is a short acting barbiturate that 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 trade 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]

Contents

[edit] Uses

[edit] 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]

In France, it is used in the treatment of insomnia, and as a preanesthetic.[4]

[edit] Unapproved/Investigational/Off-Label

Off-label uses of pentobarbital include reduction of intracranial pressure in Reye's syndrome, traumatic brain injury[1] and induction of coma in cerebral ischemia patients.[3]

[edit] Veterinary medicine

In veterinary medicine sodium pentobarbital—traded under names such as Sagatal—is used as an anaesthetic.[5] Pentobarbital is an ingredient in Equithesin.

[edit] Veterinary Euthanasia

It is used by itself, or more often in combination with complementary agents such as phenytoin, in commercial animal euthanasia[6] injectable solutions. Trade names include Euthasol, Euthatal, Beuthanasia-D and Fatal Plus.

[edit] Human Euthanasia

Pentobarbital has also been used for physician-assisted suicide. Pentobarbital was used in the Northern Territory of Australia, prior to euthanasia becoming illegal.[7]

[edit] Folklore

A pentobarbital suppository was cited in an October 2006 news article in WorldNetDaily.com as a potential murder weapon in the death of Marilyn Monroe.

[edit] Metabolism

Pentobarbital undergoes first-pass metabolism in the liver and possibly the intestines.[8]

[edit] Drug Interactions

Administration of alcohol, opioids, antihistamines, other sedative-hypnotics, and other central nervous system depressants will additively increase the sedation caused by pentobarbital.[3] The S-isomers of fluoxetine and its active metabolite, norfluoxetine, reverse the down-regulation of allopregnanolone by pentobarbital, thus reversing the loss of righting reflex, at doses 10-50 times lower than that required for serotonin reuptake.[9]

Tricyclic antidepressants decrease serum levels of pentobarbital.


[edit] References and End Notes

  1. ^ a b Pentobarbital. San Diego Reference Laboratory: Technical Help. Retrieved on 16 July 2005.
  2. ^ Lee C. Fosburgh (1997). "Imagining in Time: From this point in time: Some memories of my part in the history of anesthesia -- John S. Lundy, MD". American Association of Nurse Anesthetists Journal 65 (4): 323-8. PubMed.
  3. ^ a b c Deglin, Judith Hopfer, April Hazard Vallerand [1988] (2004-06-01). Davis's Drug Guide for Nurses, 9th edition, F. A. Davis Company, 789. ISBN 978-0-8036-1154-2. Retrieved on 2005-07-16.
  4. ^ VIDAL (2001). PENTOBARBITAL SODIQUE. Banque de Données Automatisée sur les Médicaments. Retrieved on May 2, 2006.
  5. ^ UBC Committee on Animal Care (2005). Euthanasia. SOP 009E1 - euthanasia - overdose with pentobarbital. The University of British Columbia. Retrieved on 4 October 2005.
  6. ^ Unknown (2003). ANESTHESIA AND ANALGESIA. Animal Use Protocols. University of Virginia. Retrieved on 4 October 2005.
  7. ^ Goodenough, Patrick (2002-03-26). Campaigners Rally Round Right-To-Die Woman. CNSNews.com. Retrieved on July 22, 2006.
  8. ^ Knodell, R. G., Spector MH, Brooks DA, Keller FX, Kyner WT. (December 1980). "Alterations in pentobarbital pharmacokinetics in response to parenteral and enteral alimentation in the rat". Gastroenterology 79 (6): 1211-6. PubMed.
  9. ^ Pinna, Graziano, Erminio Costa and Alessandro Guidotti (April 20, 2004). "Fluoxetine and norfluoxetine stereospecifically facilitate pentobarbital sedation by increasing neurosteroids". Proceedings of the National Academy of the United States of America 101 (16): 6222-6225. DOI:10.1073/pnas.0401479101.

[edit] External links


Barbiturates edit

Allobarbital, Amobarbital, Aprobarbital, Barbexaclone, Barbital, Butabarbital, Butalbital, Butobarbital, Cyclobarbital, Ethallobarbital, Heptabarbital, Hexobarbital, Mephobarbital, Metharbital, Methohexital, Methylphenobarbital, Pentobarbital, Phenobarbital, Primidone, Proxibarbal, Reposal, Secobarbital, Talbutal, Thiobarbital, Thiopental, Vinbarbital, Vinylbital


Anticonvulsants (N03) edit

Barbiturates: Barbexaclone, Metharbital, Methylphenobarbital, Phenobarbital, Primidone

Hydantoins: Ethotoin, Fosphenytoin, Mephenytoin, Phenytoin -- Oxazolidinediones: Ethadione, Paramethadione, Trimethadione

Succinimides: Ethosuximide, Mesuximide, Phensuximide

Benzodiazepines: Clobazam, Clonazepam, Clorazepate, Diazepam, Lorazepam, Midazolam, Nitrazepam, Temazepam

Carboxamides: Carbamazepine, Oxcarbazepine, Rufinamide -- Fatty acid derivatives: Valpromide, Valnoctamide

Carboxylic acids: Valproic acid (Sodium valproate & Valproate semisodium), Tiagabine -- GABA analogs: Gabapentin, Pregabalin, Progabide, Vigabatrin

Others:- Monosaccharides: Topiramate -- Aromatic allylic alcohols: Stiripentol -- Ureas: Phenacemide, Pheneturide -- Phenyltriazines: Lamotrigine

Carbamates: Emylcamate, Felbamate, Meprobamate -- Pyrrolidines: Brivaracetam, Levetiracetam, Nefiracetam, Seletracetam

Sulfa drugs: Acetazolamide, Ethoxzolamide, Sultiame, Zonisamide -- Propionates: Beclamide -- Aldehydes: Paraldehyde -- Bromides: Potassium bromide, Sodium bromide

In other languages