Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/12/07 17:18:45」(JST)

wiki en

Methohexital or methohexitone (marketed under the brand name Brevital) is a drug which is a barbiturate derivative. It is classified as short-acting, and has a rapid onset of action. It is similar in its effects to sodium thiopental, a drug with which it competed in the market for anaesthetics.

Pharmacology

Methohexital binds to a distinct site which is associated with Cl⁻ ionophores at GABA_A receptors.^[1] This increases the length of time which the Cl⁻ ionopores are open, thus causing an inhibitory effect.

Metabolism of methohexital is primarily hepatic (i.e., taking place in the liver) via demethylation and oxidation.^{[citation needed]} Side-chain oxidation is the primary means of metabolism involved in the termination of the drug's biological activity.

Protein binding is approximately 73% for methohexital.^{[citation needed]}

Indications

Methohexital is primarily used to induce anesthesia, and is generally provided as a sodium salt (i.e. methohexital sodium). It is only used in hospital or similar settings, under strict supervision.^{[citation needed]} It has been commonly used to induce deep sedation or general anesthesia for surgery and dental procedures. Unlike many other barbiturates, Methohexital actually lowers the seizure threshold, a property that make it particularly useful when anesthesia is provided for a electroconvulsive therapy (ECT). And rapid recovery rate with consciousness being gained within three to seven minutes after induction and full recovery within 30 minutes is a major advantage over other ECT barbiturates (Schulgasser and Borowitz 1963).

Synthesis

Methohexital, 5-allyl-1-methyl-5-(1-methyl-2-pentinyl barbituric acid, is synthesized in the classic manner of making barbituric acid derivatives, in particular by the reaction of malonic ester derivatives with derivatives of urea.

Methohexital synthesis: W.J. Doran, U.S. Patent 2,872,448 (1959).

The resulting allyl-(1-methyl-2-pentynyl) malonic ester is synthesized by subsequent alkylation of the malonic ester itself, beginning with 2-bromo-3-hexyne, which gives (1-methyl-2-pentynyl)malonic ester, and then by allylbromide. In the final step, reaction of the disubstituted malonic ester with N-methylurea gives desired methohexital.

References

^ Katzung, Bertram G., Basic and Clinical Pharmacology, 10th ed., p. 406-407

^[1]

External links

RxList.com - Methohexital
Drugs.com - Methohexital Sodium
DrugLib.com - Brevital (Methohexital Sodium)

^ SCHULGASSER, H; BOROWITZ, A (1963). "Methohexital anaesthesia in electroconvulsive therapy". South African Medical Journal 37: 870.

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 成人におけるてんかんの外科的治療 surgical treatment of epilepsy in adults
2. 成人における処置時の鎮静 procedural sedation in adults
3. 小児に対する手術室外での鎮静処置に使用する薬剤 pharmacologic agents for pediatric procedural sedation outside of the operating room
4. 小児に対する手術室外での鎮静処置に使用する薬剤の選択 selection of medications for pediatric procedural sedation outside of the operating room
5. 危篤状態の成人における鎮静鎮痛剤：選択、開始、維持、および離脱 sedative analgesic medications in critically ill adults selection initiation maintenance and withdrawal

English Journal

[Perstimulus asystole during electroconvulsive therapy: Clinical case and critical literature review].

Roche NC1, Raynaud L2, Bompaire F3, Lucas JJ4, Auxéméry Y5.
L'Encéphale.Encephale.2016 Feb;42(1):59-66. doi: 10.1016/j.encep.2015.06.004. Epub 2015 Sep 6.
INTRODUCTION: Electroconvulsive therapy (ECT) is most frequently indicated for episodes of melancholic depression, but is also useful in the treatment of maniac syndrome and some schizophrenia subtypes. ECT is part of the treatment of movement disorders, neuroleptic malignant syndrome and even in th
PMID 26350554

A Bayesian framework systematic review and meta-analysis of anesthetic agents effectiveness/tolerability profile in electroconvulsive therapy for major depression.

Fond G1,2, Bennabi D3,2, Haffen E3,2, Brunel L1, Micoulaud-Franchi JA4, Loundou A5, Lançon C4,5,2, Llorca PM2,6, Auquier P5,7, Boyer L5,7.
Scientific reports.Sci Rep.2016 Jan 25;6:19847. doi: 10.1038/srep19847.
The aim of this study was to assess the efficacy and tolerability/acceptability of 6 anesthetic agents in ECT for depressive disorders. We systematically reviewed 14 double-blind randomized controlled trials (610 participants). Efficacy was measured by the mean scores on validated depression scales
PMID 26806849

Evaluation of Etomidate for Seizure Duration in Electroconvulsive Therapy: A Systematic Review and Meta-analysis.

Singh PM1, Arora S, Borle A, Varma P, Trikha A, Goudra BG.
The journal of ECT.J ECT.2015 Dec;31(4):213-25. doi: 10.1097/YCT.0000000000000212.
The optimum induction agent for anesthesia for electroconvulsive therapy (ECT) has been long debated. Ideal agent should be short acting with minimal suppression of seizure potentials. Recent studies have suggested longer seizure duration with etomidate in comparison to propofol, thiopental, and met
PMID 25634566

Japanese Journal

Management of poor postictal suppression during electroconvulsive therapy with propofol anesthesia : a report of two cases

Journal of anesthesia 26(6), 925-927, 2012-12-20
NAID 10031147431

Effects of propofol vs methohexital on neutrophil function and immune status in critically ill patients

Journal of anesthesia 20(2), 86-91, 2006-05-20
NAID 10019167515

The comparative effects of sevoflurane and methohexital for electroconvulsive therapy

J ECT 19, 221-225, 2003
NAID 30007529904

Related Pictures

Buy Brevital Sodium 500 mg (Methohexital Sodium) - NEMBUTAL HUB methohexital injection : Uses, Side Effects, Interactions, Pictures, Warnings & Dosing Anesthesia Medicinal Chemistry Lectures Notes: January 2012 Brevital®, Methohexital Sodium, Injection, 500 mg/50 ml Strength, 50 ml, 1/Pkg, NDC 53314 Brevital? Sodium (Methohexital Sodium for Injectio - Drugs (C-III, IV, V) Methohexital : Therapeutic uses, Dosage & Side Effects - DoctorAlerts Methohexital - brand name list from Drugs.com

★リンクテーブル★

リンク元	「メトヘキシタール」
拡張検索	「methohexital sodium」

「メトヘキシタール」

Methohexital
Systematic (IUPAC) name
	5-hex-3-yn-2-yl-1- methyl-5-prop-2-enyl-1, 3-diazinane-2,4,6-trione
Clinical data
AHFS/Drugs.com	Consumer Drug Information
Pregnancy; category	B (USA);
Legal status	AU: S4 (Prescription only); Schedule IV;
Routes of; administration	Intravenous, rectal
Pharmacokinetic data
Bioavailability	I.V. ~100%; Rectal ~17%
Metabolism	Hepatic
Biological half-life	5.6 ± 2.7 minutes
Excretion	?
Identifiers
CAS Number	151-83-7
ATC code	N01AF01 N05CA15
PubChem	CID: 9034
IUPHAR/BPS	7233
DrugBank	DB00474
ChemSpider	8683
UNII	E5B8ND5IPE
KEGG	D04985
ChEBI	CHEBI:102216
ChEMBL	CHEMBL7413
Chemical data
Formula	C14H18N2O3
Molecular mass	262.304
	SMILES O=C1N(C(=O)NC(=O)C1(C\C=C)C(C#CCC)C)C ;
	InChI InChI=1S/C14H18N2O3/c1-5-7-8-10(3)14(9-6-2)11(17)15-13(19)16(4)12(14)18/h6,10H,2,5,9H2,1,3-4H3,(H,15,17,19) ; Key:NZXKDOXHBHYTKP-UHFFFAOYSA-N ;
(what is this?) (verify)