Methohexital
Lua error in Module:Infobox at line 314: malformed pattern (missing ']'). 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 GABAA 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.
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
External links
- RxList.com - Methohexital
- Drugs.com - Methohexital Sodium
- DrugLib.com - Brevital (Methohexital Sodium)
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
