Ultra-short Acting Barbitutrates: Methohexital sodium, Thiamylal sodium, Thiopental sodium

Ultra-short Acting Barbiturates

These are barbiturates that act very rapidly, typically within minutes.

They are used for anesthesia induction and short-term procedures such as intubation.

Short-acting barbiturates

These barbiturates act relatively quickly, typically within an hour. Therefore, they are used for general anesthesia and more lengthy procedures. Examples of short-acting barbiturates include pentobarbital and propofol.

Methohexital sodium

Methohexital sodium is a barbiturate that is used for general anesthesia.

It has a rapid onset of action, typically within minutes, and a short duration of action, typically lasting around 30 minutes.

Therefore, Methohexital sodium is also known as Brevital Sodium.

Side effects

Methohexital sodium can also cause paradoxical excitement, a state of increased energy and activity.

Interactions

Methohexital sodium can interact with other drugs such as alcohol, opioids, and sedatives.

It can also interact with certain medical conditions, such as sleep apnea.

The spectrum of action

Methohexital sodium spectrum of action refers to the range of activities that the drug can produce.

The maintenance of working and functioning included the desired effects and undesired effects as well.

• Methohexital sodium has a broad spectrum of action, producing various effects in the body.
• For example, it is a central nervous system depressant, meaning that it slows down the activity of the brain and nervous system.
• It also has analgesic (pain-relieving), sedative, and hypnotic effects.

Duration of action

Methohexital sodium has a short duration of action, typically lasting around 30 minutes.

Unfortunately, this means that the effects of the drug wear off relatively quickly.

Thiamylal sodium

• Thiamylal sodium is available as a generic drug.
• The dose range for thiamylal sodium is 2.5 to 10 mg/kg intravenously.
• Thiamylal sodium can be administered as a bolus or as an infusion.
• It should also not be used in nursing mothers because thiamylal sodium is excreted in breast milk.

Thiopental sodium

• Thiopental sodium (Pentothal) is a barbiturate formerly used as an anesthetic.
• So far, the United States has stopped the usage of Pentothal but it is still available in other countries.
• Pentothal can be given by injection into a muscle or vein.
• When given by injection, Pentothal begins to work within minutes, and its effects last for about half an hour.
• Pentothal should not be used in people with porphyria or liver disease.

Uses

• Pentothal is used for general anesthesia.
• It is sometimes used before surgery to make you sleep during the procedure.
• Pentothal may also be used for other purposes as determined by your doctor.

Precautions

• Before using Pentothal, tell your doctor if you are allergic to any drugs or if you have porphyria or liver disease.
• Pentothal should not be used in pregnant women or children.

Mode of action

Barbiturates like Pentothal work by depressing the central nervous system.

This causes general anesthesia, which means you will be asleep and unaware of pain during surgery.

1. Narcotics such as morphine

2. Antihistamines such as diphenhydramine (Benadryl)

3. Sedatives such as diazepam (Valium)

4. Bronchodilators such as albuterol (Ventolin)

5. Tricyclic antidepressants such as amitriptyline (Elavil)

6. MAO inhibitors such as isocarboxazid (Marplan)

7. Warfarin (Coumadin)

8. Digoxin (Lanoxin)

The spectrum of action

• Barbiturates like Pentothal have a broad spectrum of action, which can be used for various purposes.
• Pentothal is most commonly used as an anesthetic to put you to sleep during surgery.
• However, it can also be used to relieve pain and anxiety. Pentothal may also be used to calm a person with a seizure.

History
Pentothal was first developed in the 1930s. It was one of the first anesthetics to be used in surgery.

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