Methohexital is a barbiturate (bar-BIT-chur-ate) that is used to cause you to fall asleep before a surgery or other medical procedure.

Methohexital may also be used for purposes not listed in this medication guide.

Avoid driving or operating machinery for 8 to 12 hours after you awake from anesthesia.

Methohexital is injected into a muscle or a vein. This medication is also given rectally when used in young children.

A healthcare provider will give you this medicine.

Tell your medical caregivers if you feel any burning or pain when methohexital is injected.

Methohexital should make you fall asleep very quickly.

Your breathing, blood pressure, oxygen levels, and other vital signs will be watched closely. You will also be watched closely while you are coming out of the anesthesia.

Drowsiness may last for several hours. You will need someone to drive you home from after you receive methohexital.

Usual Adult Dose for Anesthesia:

Induction of Anesthesia:
-Administer 1 to 1.5 mg/kg of a 1% solution IV a rate of about 1 mL/5 seconds; gaseous anesthetics and/or skeletal muscle relaxants may be administered concomitantly.
-The induction dose usually provides anesthesia for 5 to 7 minutes.

Maintenance of Anesthesia:
-Administer intermittent IV injections of 20 to 40 mg of the 1% solution every 4 to 7 minutes OR administer 3 mL of a 0.2% solution by continuous IV infusion per minute.
-Individualize the rate of flow for each patient.
-For longer surgical procedures, a gradual reduction in the rate of administration is recommended.
-Other parenteral agents (e.g., narcotic analgesics) are usually used with this drug during longer procedures.

Uses:
-For IV induction of anesthesia prior to the use of other general anesthetic agents.
-For IV induction of anesthesia and as an adjunct to subpotent inhalational anesthetic agents (e.g., nitrous oxide in oxygen) for short surgical procedures; this drug may be given by infusion or intermittent injection.
-For use along with other parenteral agents, usually narcotic analgesics, to supplement subpotent inhalational anesthetic agents (e.g., nitrous oxide in oxygen) for longer surgical procedures.
-As IV anesthesia for short surgical, diagnostic, or therapeutic procedures associated with minimal painful stimuli.
-To induce a hypnotic state.

Usual Pediatric Dose for Anesthesia:

One month or older:
Induction of Anesthesia:
IM: 6.6 to 10 mg/kg using a 5% solution
Rectal: 25 mg/kg using a 1% solution

Uses: Pediatric patients 1 month and older:
-For IM or rectal induction of anesthesia prior to the use of other general anesthetic agents.
-For IM or rectal induction of anesthesia and as an adjunct to subpotent inhalational anesthetic agents for short surgical procedures.
-As IM or rectal anesthesia for short surgical, diagnostic, or therapeutic procedures associated with minimal painful stimuli.

You should not be treated with methohexital if you are allergic to it, or if you have:

• porphyria (a genetic enzyme disorder that causes symptoms affecting the skin or nervous system); or

• an allergy to other barbiturates (butabarbital, pentobarbital, phenobarbital, secobarbital, and others).

Tell your doctor if you have ever had:

• epilepsy or other seizure disorder;

• asthma or chronic obstructive pulmonary disease (COPD);

• liver or kidney disease;

• anemia (lack of red blood cells);

• an endocrine disorder;

• high or low blood pressure;

• heart disease, congestive heart failure; or

• circulation problems.

Tell your doctor if you are pregnant.

Anesthesia may affect brain development in a young child or unborn baby (when used in the mother), leading to learning or behavior problems later in life. Long surgeries or repeated procedures pose the highest risks.

Anesthesia may still be necessary for a life-threatening condition, medical emergency, or surgery to correct a birth defect. Your doctor can give inform you about all medicines given during a surgery or procedure.

Ask a doctor if it is safe to breastfeed while using methohexital.

Methohexital is used as a single dose and does not have a daily dosing schedule.

In a medical setting an overdose would be treated quickly.

This medication may impair your thinking or reactions. Avoid driving or operating machinery for 8 to 12 hours after you awake from anesthesia.

Avoid drinking alcohol for a short time after receiving methohexital. Dangerous side effects could occur.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your medical caregivers right away if you have:

• severe burning or swelling where the medicine was injected;

• fast heartbeats;

• a light-headed feeling, like you might pass out;

• muscle twitching; or

• confusion, anxiety, or restless feeling when coming out of anesthesia.

Common side effects of methohexital may include:

• drowsiness;

• nausea, vomiting, stomach pain;

• chills or shivering;

• coughing, hiccups; 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.

Tell your doctor about all your other medicines, especially:

• phenytoin or other seizure medications;

• a blood thinner--warfarin, Coumadin, Jantoven; or

• steroid medicine--prednisone, dexamethasone, prednisolone, and 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.