Methohexital is an ultrashort-acting barbiturate widely used in dentistry because of its rapid onset, predictable effects, and short duration of action. It was marked under the name brevital sodium for the intravenous anaesthesia. It has also been commonly used to induce deep sedation. Like other barbiturates, methohexital exerts its effects through the gamma-aminobutyric acid (GABA) receptor complex. By binding to its own receptor on the complex, methohexital augments the inhibitory effect of GABA on neurons and additionally can exert a similar effect independent of GABA.

Methohexital:
https://drugs.ncats.io/drug/E5B8ND5IPE

What is methohexital?
Methohexital is a barbiturate. Methohexital slows the activity of your brain and nervous system. Methohexital is used to cause you to fall asleep before a surgery or other medical procedure.

Important Information:

You should not use methohexital if you have a history of porphyria (a genetic enzyme disorder that causes symptoms affecting the skin or nervous system). This medication may impair your thinking or reactions. Avoid driving or operating machinery for 8 to 12 hours after you awake from anesthesia.

Do not drink alcohol just after receiving methohexital. Dangerous side effects could occur.

Interactions:

Drug Interactions (113) Alcohol/Food Interactions (1)

What other drugs will affect Methohexital?
Tell your doctor about all your other medicines, especially:

• phenytoin or other seizure medications
• a blood thinner:
  • warfarin
  • Coumadin
  • Jantoven
• steroid medicine:
  • prednisone
  • dexamethasone
  • prednisolone
  • others

This list is not complete. Other drugs may affect methohexital, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

A total of 113 drugs are known to interact with Methohexital.

• 9 major drug interactions
  • anisindione
  • dicumarol
  • ethanol
  • hemin
  • isocarboxazid
  • phenelzine
  • selegiline
  • tranylcypromine
  • warfarin
• 78 moderate drug interactions
• 26 minor drug interactions

Methohexital:
https://www.drugs.com/mtm/methohexital.html

Indications:
BREVITAL can be used in adults as follows:

Brevital (methohexital sodium for injection)

Side Effects:
Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
RxList
brevital sodium (methohexital sodium for injection) drug : https://www.rxlist.com/brevital-sodium-drug.htm#indications
Tell your caregivers right away if you have: severe burning or swelling where the medicine was injected fast heartbeats numbness or tingly feeling a light-headed feeling, like you might pass out weak or shallow breathing confusion, anxiety, or restless feeling when coming out of anesthesia
Side effects such as confusion, depression, or excitement may be more likely in older adults and those who are ill or debilitated.
Common side effects may include: drowsiness nausea, vomiting, stomach pain chills or shivering coughing, hiccups muscle twitching mild skin rash or itching
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

DESCRIPTION:
Ultra-short-acting highly lipophilic barbiturate; faster onset of action and recovery time vs thiopental and twice as potent; used alone as an anesthetic for short procedures that are relatively painless, as an inducing agent, or as an adjunct to regional anesthesia.

Brevital (Methohexital) Sodium

Maximum Dosage:
Prescribers Digital Reference
Methohexital Sodium Drug Summary: https://www.pdr.net/drug-summary/Brevital-Sodium-methohexital-sodium-1769
Adults	Dose depends on indication and is titrated to effect.
Elderly	Dose depends on indication and is titrated to effect.
Adolescents	Dose depends on indication and is titrated to effect.
Children	Dose depends on indication and is titrated to effect.
Infants	Dose depends on indication and is titrated to effect.
Neonates	Safety and efficacy have not been established.

Breastfeeding:

Summary of Use During Lactation:
Amounts of methohexital in milk are very small.

Existing data indicate that no waiting period is required before resuming breastfeeding after a single dose of methohexital.

Breastfeeding can be resumed as soon as the mother has recovered sufficiently to nurse.

When a combination of anesthetic agents is used for a procedure, follow the recommendations for the most problematic medication used during the procedure.

Alternate Drugs to Consider:

• Dexmedetomidine
• Etomidate
• Propofol
• Thiopental

Methohexital Drug Levels and Effects:
https://www.ncbi.nlm.nih.gov/books/NBK501299/

Pregnancy:
There are no adequate and well-controlled studies in pregnant women; published studies in pregnant primates demonstrate that administration of anesthetic and sedation drugs that block NMDA receptors and/or potentiate GABA activity during the period of peak brain development increases neuronal apoptosis in the developing brain of the offspring when used for longer than 3 hours; clinical significance not clear; however, studies in juvenile animals suggest neuroapoptosis correlates with long-term cognitive deficits.

Brevital Methohexital (Rx)

Black Box Warnings:
Methohexital (Rx): https://reference.medscape.com/drug/brevital-methohexital-343090
Methohexital should be used in hospital or ambulatory care settings that can provide continuous monitoring of respiratory (eg, pulse oximetry) and cardiac function Resuscitative drugs and age- and size-appropriate equipment for bag valve mask ventilation and intubation and personnel trained in their use and skilled in airway management should be readily available For deeply sedated patients, a designated individual other than the practitioner performing the procedure should be present to continuously monitor the patient

What should I watch for while using this medicine?
Your condition will be monitored carefully while you are receiving this medicine.

You may get drowsy or dizzy. Do not drive for at least 8 to 12 hours after you are treated with this medicine. Do not use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.

Methohexital Injection:
https://www.nationwidechildrens.org/family-resources-education/family-resources-library/methohexital-injection

Side Effects:

• Heart: Circulatory depression, vein inflammation, low blood pressure, fast heart rate and epilepsy associated with cardio respiratory arrest.
• Respiratory: Respiratory depression, asthma, hiccups and difficulty in breathing.
• Central Nervous System: Twitching, injury to nerves adjacent to injection site, confusion, restlessness and anxiety may occur.
• Gastrointestinal: Nausea, vomiting, abdominal pain and abnormal liver function tests.
• Allergic: Redness, itching and hives.
• Other: Pain at injection site, salivation, headache and nose inflammation.

Methohexital - Indications, Dosage, Side Effects and Precautions :
https://www.medindia.net/doctors/drug_information/methohexital.htm

WARNING:
Brevital should be used only in hospital or ambulatory care settings that provide for continuous monitoring of respiratory (e.g. pulse oximetry) and cardiac function. Immediate availability of resuscitative drugs and age- and size-appropriate equipment for bag/valve/mask ventilation and intubation and personnel trained in their use and skilled in airway management should be assured. For deeply sedated patients, a designated individual other than the practitioner performing the procedure should be present to continuously monitor the patient.

http://www.druglib.com/druginfo/brevital/

BREVITAL (methohexital sodium) for injection, USP Label (PDF 12 pages):
https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/011559s051lbl.pdf

Alternate Names:
METHOHEXITAL, METHOHEXITONE, ALPHA-DL-1-METHYL-5-ALLYL-5-(1'-METHYLPENTYN-2-YL)BARBITURIC ACID, METHOHEXITALUM, (+-)-5-ALLYL-1-METHYL-5-(1-METHYL-2-PENTYNYL)BARBITURIC ACID, 5-ALLYL-1-METHYL-5-(1-METHYL-2-PENTYNYL)-2,4,6(1H,3H,5H)-PYRIMIDINETRIONE, 5-ALLYL-5-(3-HEXYN-2-YL)-1-METHYLBARBITURIC ACID, 1-METHYL-5-(1-METHYLPENT-2-YNYL)-5-PROP-2-ENYL-HEXAHYDROPYRIMIDINE-2,4,6-TRIONE, METOHEXITAL, 5-ALLYL-1-METHYL-5-(1-METHYL-PENT-2-YNYL)-PYRIMIDINE-2,4,6-TRIONE

Methohexital Drug Record:
http://www.dgidb.org/drugs/METHOHEXITAL

Administration:
Methohexital has a variety of administration routes, including rectal, IV, and IM use.

• Standard adult dosing for anesthesia induction is 50 to 120 mg IV as a bolus. General anesthesia maintenance calls for 20 to 40 mg IV every 4 to 7 minutes as needed. In pediatrics, general anesthesia induction dosing is 6.6 to 10 mg/kg IM injection once. Alternately, 25 mg/kg as a single dose rectally is an option.
• In pediatrics, methohexital has found application in procedural sedation for obtaining imaging at doses between 0.5 mg/kg to 2.0 mg /kg. The use of rectal methohexital is predominantly in the pediatric population; one study reports a dose of 30 mg/kg of 10% methohexital caused 85% of children to fall asleep. The induction dose for methohexital for electroconvulsive therapy is 1.5 mg/kg.
• After IV administration of methohexital, peak brain concentrations occur at the 30-second mark and steadily decline as the drug gets redistributed to other tissues. Five minutes after administration, half of the initial concentration is in the grey matter. The duration of action for methohexital is 4 to 7 minutes. Metabolism of methohexital occurs in the liver where the molecule undergoes oxidation of the side chain at carbon 5 of the benzene resulting in the inactive metabolite hydroxymethohexital. In summary, the disappearance of methohexital from the bloodstream is attributable to both liver inactivation and redistribution, but redistribution plays a greater role.

Methohexital:
https://www.ncbi.nlm.nih.gov/books/NBK544291/

BREVITAL SODIUM - methohexital sodium injection, powder, lyophilized, for solution Drug Label Information:
https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=eccd8340-ead3-4363-8902-0c19d33aa2ac

Barbiturate derivative - It is classified as short-acting, and has a rapid onset of action. 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. 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 an 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.