Pentobarbital 2246554 223756358 2008-07-05T17:14:39Z CielProfond 1520890 /* Veterinary Euthanasia */ Added Euthanyl {{Drugbox| | IUPAC_name = ''5-Ethyl-5-(1-methylbutyl)-<BR>2,4,6(1''H'',3''H'',5''H'')-pyrimidinetrione'' | image = Pentobarbital-2D-skeletal.png | width = 247 | CAS_number = 76-74-4 | ATC_prefix = N05 | ATC_suffix = CA01 | ATC_supplemental = | PubChem = 4737 | DrugBank = APRD01174 | C = 11 | H = 18 | N = 2 | O = 3 | molecular_weight = 226.1317 | bioavailability = 70-90% oral; 90% rectal | protein_bound = 20-45% | metabolism = [[Liver|Hepatic]] | elimination_half-life = 15-48 hours | excretion = [[Kidney|Renal]] | pregnancy_category = D ([[United States|USA]]) | legal_status = [[United States|USA]]: [[Schedule II]] (oral and [[parenteral]]); [[Schedule III]] (rectal) | routes_of_administration = 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.<ref name=solubility>{{cite web | url = http://www.sdrl.com/druglist/pentobarbital.html | title = Pentobarbital | work = San Diego Reference Laboratory: Technical Help | accessdaymonth = 16 July | accessyear = 2005 }}</ref> 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&mdash;'''N'''a (sodium) + '''e'''thyl + '''m'''ethyl + '''but'''yl + '''al''' (common suffix for barbiturates).<ref name=Nembutal>{{cite journal | author=Lee C. Fosburgh | title=Imagining in Time: From this point in time: Some memories of my part in the history of anesthesia -- John S. Lundy, MD | journal=American Association of Nurse Anesthetists Journal | volume=65 | issue=4 | year=1997 | pages=323–8 | pmid = 9281913 | url = https://www.aana.com/archives/imagine/1997/08imagine97.asp | format={{Dead link|date=May 2008}}}}</ref> ==Uses== ===Approved=== Pentobarbital's [[Food and Drug Administration|FDA]] approved human uses include treatment of [[seizure]]s and preoperative (and other) [[sedation]]; it is also approved as a short-term [[hypnotic]].<ref name=approved_USA>{{cite book | last = Deglin | first = Judith Hopfer | coauthors = April Hazard Vallerand | title = Davis's Drug Guide for Nurses | origyear = 1988 | url = http://www.drugguide.com/monograph_library/additional_monographs/pentobarbital.htm | accessdate = 2005-07-16 | edition = 9th edition | date = 2004-06-01 | publisher = F. A. Davis Company | id = ISBN 978-0-8036-1154-2 | pages = 789}}</ref> In France and the Netherlands, it is no longer used in the treatment of [[insomnia]], nor as a preanesthetic.<ref name=approved_France>{{cite web | author = VIDAL | year = 2001 | title = PENTOBARBITAL SODIQUE | work = Banque de Données Automatisée sur les Médicaments | url = http://www.biam2.org/www/Sub2971.html | accessmonthday = May 2 | accessyear = 2006}}</ref> ===Unapproved/Investigational/Off-Label=== Off-label uses of pentobarbital include reduction of intracranial pressure in [[Reye's syndrome]], traumatic brain injury<ref name=solubility /> and induction of coma in cerebral [[ischemia]] patients.<ref name=approved_USA /> ===Veterinary Medicine=== In [[veterinary medicine]], sodium pentobarbital&mdash;traded under names such as ''Sagatal''&mdash;is used as an [[anaesthetic]].<ref name=veterinary_anesthesic>{{cite web | author=UBC Committee on Animal Care | year=2005 | title=Euthanasia | work=SOP 009E1 - euthanasia - overdose with pentobarbital | publisher=The University of British Columbia | url=http://www.acc.ubc.ca/SOP/SOPeuthp.html | accessdaymonth=4 October | accessyear=2005}}</ref> Pentobarbital is an ingredient in [[Equithesin]]. ===Veterinary Euthanasia=== It is used by itself, or more often in combination with complementary agents such as [[phenytoin]], in commercial [[animal euthanasia]]<ref name=veterinary_euthanasia>{{cite web |author=Unknown | year=2003 | title=ANESTHESIA AND ANALGESIA | work=Animal Use Protocols | publisher=University of Virginia | url=http://www.healthsystem.virginia.edu/internet/ccm/Anesth/aneshome.cfm | accessdaymonth=4 October | accessyear=2005}}</ref> injectable solutions. Trade names include ''Euthasol'', ''Euthatal'', ''Euthanyl'' (in Canada), ''Beuthanasia-D'', and ''Fatal Plus''. ===Human Euthanasia=== In the [[Netherlands]], a pentobarbital elixer is used as an alternative for patients who wish to take the barbiturate needed for the lethal cocktail themselves, instead of having it administered intravenously, in which case [[thiopenthal]] is used. Pentobarbital has no medical use anymore in the Netherlands, and is only used for euthanasia. Pentobarbital has also been used for physician-assisted suicide. It is commonly used in [[Oregon]] for [[physician assisted suicide]].<ref name=human_euthanasia>{{cite web|url=http://www.cnsnews.com/Culture/Archive/200203/CUL20020326a.html |title=Campaigners Rally Round Right-To-Die Woman |accessmonthday=July 22 |accessyear=2006 |last=Goodenough |first=Patrick |date=2002-03-26 |work=CNSNews.com}}</ref>, and is also used by [[Dignitas (euthanasia group)]]. Pentobarbital was also used for this purpose in the Northern Territory of Australia, prior to euthanasia becoming illegal in that region. ==Folklore== A pentobarbital suppository was cited in an October 2006 [http://wnd.com/news/article.asp?ARTICLE_ID=52493 news article] in [http://wnd.com/ WorldNetDaily.com] as the cause of death of [[Marilyn Monroe]]. [[The Clash]] makes a reference to it in the song [[The Right Profile]] from the album [[London Calling]] in which the lyrics read "Nembutal numbs it all, but I prefer... alcohol!" The song "[[Yellow Submarine (song)|Yellow Submarine]]" by [[The Beatles]] is rumored to reference to Nembutal due to the color and shape of the capsules. However, [[Paul McCartney]] has denied this, stating that he had written the song as a children's tune. ==Metabolism== [[Image:pentobarbital DOJ.jpg|frame|right]] Pentobarbital undergoes [[metabolism|first-pass metabolism]] in the liver and possibly the intestines.<ref name=first-pass>{{cite journal | first = R. G. | last = Knodell | coauthors = Spector MH, Brooks DA, Keller FX, Kyner WT. | month = December | year = 1980 | title = Alterations in pentobarbital pharmacokinetics in response to parenteral and enteral alimentation in the rat | journal = Gastroenterology | volume = 79 | issue = 6 | pages = 1211–6 | pmid = 6777235}}</ref> ==Drug Interactions== Administration of [[alcohol]], [[opioid]]s, [[antihistamine]]s, other [[sedative|sedative-hypnotic]]s, and other [[central nervous system]] depressants will greatly increase the sedation caused by pentobarbital.<ref name=approved_USA /> <!-- The S-[[isomer]]s 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.<ref name=not_with_fluoxetine>{{cite journal | first = Graziano | last = Pinna | coauthors = Erminio Costa and Alessandro Guidotti | date = April 20, 2004 | title = Fluoxetine and norfluoxetine stereospecifically facilitate pentobarbital sedation by increasing neurosteroids | journal = Proceedings of the National Academy of the United States of America | volume = 101 | issue = 16 | pages = 6222–6225 | doi = 10.1073/pnas.0401479101| url = http://www.pnas.org/cgi/content/full/101/16/6222 | pmid = 15069199}}</ref> --> <!-- caffeine * chloramphenicol * chlorpromazine * cyclophosphamide * cyclosporine * digitoxin * doxorubicin * doxycycline * methoxyflurane * metronidazole * medicines for anxiety or sleeping problems * medicines for hay fever and other allergies * medicines for high blood pressure * medicines for mental depression * medicines for pain * medicines that help the heart to beat regularly * quinine * seizure (convulsion) or epilepsy medicine * steroid medicines such as prednisone or cortisone * theophylline * warfarin--> ==References and End Notes== {{reflist}} ==External links== {{Barbiturates}} {{Anticonvulsants}} {{Hypnotics and sedatives}} [[Category:Anticonvulsants]] [[Category:barbiturates]] [[de:Pentobarbital]] [[gl:Pentobarbital]] [[ja:ペントバルビタール]] [[pt:Pentobarbital]] [[ru:Пентобарбитал]] [[fi:Pentobarbitaali]] [[sv:Pentobarbital]]