2845 Methohexital Methohexital is only found in individuals that have used or taken this drug. It is an intravenous anesthetic with a short duration of action that may be used for induction of anesthesia. Methohexital binds at a distinct binding site associated with a Cl^- ionopore at the GABA_A receptor, increasing the duration of time for which the Cl^- ionopore is open. The post-synaptic inhibitory effect of GABA in the thalamus is, therefore, prolonged. 151-83-7 9034 C14H18N2O3 262.131740 White powder. 5.24e-02 g/L Parenteral (intramuscular, intravenous). The absolute bioavailability following rectal administration of methohexital is 17%. Methohexital binds at a distinct binding site associated with a Cl^- ionopore at the GABA_A receptor, increasing the duration of time for which the Cl^- ionopore is open. The post-synaptic inhibitory effect of GABA in the thalamus is, therefore, prolonged. Metabolism occurs in the liver through demethylation and oxidation. Side-chain oxidation is the most important biotransformation involved in termination of biologic activity. Route of Elimination: Excretion occurs via the kidneys through glomerular filtration. Half Life: 5.6 ± 2.7 minutes No indication of carcinogenicity to humans (not listed by IARC). Methohexital is indicated for use as an intravenous anaesthetic. It has also been commonly used to induce deep sedation. It is only used in hospital or similar settings, under strict supervision. They cause slurred speech, disorientation and "drunken" behavior. They are physically and psychologically addictive. The onset of toxicity following an overdose of intravenously administered methohexital will be within seconds of the infusion. If methohexital is administered rectally or is ingested, the onset of toxicity may be delayed. The manifestations of an ultrashort-acting barbiturate in overdose include central nervous system depression, respiratory depression, hypotension, loss of peripheral vascular resistance, and muscular hyperactivity ranging from twitching to convulsive-like movements. Other findings may include convulsions and allergic reactions. Establish an airway and ensure oxygenation and ventilation. Resuscitative measures should be initiated promptly. For hypotension, intravenous fluids should be administered and the patient's legs raised. If desirable increase in blood pressure is not obtained, vasopressor and/or inotropic drugs may be used as dictated by the clinical situation. For convulsions, diazepam intravenously and phenytoin may be required. If the seizures are refractory to diazepam and phenytoin, general anesthesia and paralysis with a neuromuscular blocking agent may be necessary. Protect the patient's airway and support ventilation and perfusion. Meticulously monitor and maintain, within acceptable limits, the patient's vital signs, blood gases, serum electrolytes, etc. Absorption of drugs from the gastrointestinal tract may be decreased by giving activated charcoal, which, in many cases, is more effective than emesis or lavage; consider charcoal instead of or in addition to gastric emptying. Repeated doses of charcoal over time may hasten elimination of some drugs that have been absorbed. Safeguard the patient's airway when employing gastric emptying or charcoal. (L1712) 2009-07-21T20:26:59Z 2014-12-24T20:25:51Z Methohexital C07844 102216 Methohexital DB00474 true CCC#CC(C)C1(CC=C)C(O)=NC(=O)N(C)C1=O C14H18N2O3 InChI=1/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) InChIKey=NZXKDOXHBHYTKP-UHFFFAOYNA-N 262.3043 262.131742452 Exogenous Solid 1.8 HMDB14617 CHEMBL7413 8683