March 21, 2017

Methoxyflurane inhalation liquid

What is methoxyflurane inhalation liquid?

METHOXYFLURANE (Penthrane®) was used for general anesthesia during surgery and cesarean section. General anesthesia is commonly used for extensive and long surgeries, but also can be used in shorter and limited procedures, including labor and delivery. Generic methoxyflurane inhalation liquid is not yet available.

NOTE: This drug is discontinued in the United States.

What should my health care professional know before I receive methoxyflurane?

They need to know if you have any of these conditions:

  • diabetes

  • eclamsia or preeclampsia

  • history of malignant hyperthermia

  • kidney disease or urinary problems

  • liver disease

  • myasthenia gravis

  • an unusual or allergic reaction to methoxyflurane, or other anesthetics

  • pregnant or trying to get pregnant

  • breast-feeding

How should I use this medicine?

Methoxyflurane is given through inhalation (breathing the gas into the lungs) by trained anesthesia professionals in a controlled environment like an operating room before and during surgery or procedures. Since there is no one ideal general anesthetic, a combination of drugs that are either injected or inhaled are typically used.

What if I miss a dose?

This does not apply.

What drug(s) may interact with methoxyflurane?

  • alcohol

  • amiodarone

  • doxapram

  • herbal products, including St. John's wort

  • isoniazid, INH

  • levodopa

  • medicines for colds, breathing difficulties, or weight loss

  • medicines for high blood pressure, including beta-blockers

  • medicines that improve muscle strength or tone for conditions like myasthenia gravis

  • medicines for seizures

  • rifampin

  • theophylline

  • warfarin

Tell your prescriber or health care professional about all other medicines you are taking, including non-prescription medicines, nutritional supplements, or herbal products. Also tell your prescriber or health care professional if you are a frequent user of drinks with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way your medicine works. Check with your health care professional before stopping or starting any of your medicines.

What should I watch for while taking methoxyflurane?

You will be closely monitored following anesthesia with methoxyflurane.

Methoxyflurane can affect your ability to drive or do anything that needs mental alertness for about 24 hours after anesthesia. Do not attempt to drive yourself home if you have received methoxyflurane for minor outpatient surgery. You may feel dizzy and lightheaded. To reduce the risk of dizzy or fainting spells, do not sit up or stand up quickly, especially if you are an older patient. Alcohol can make you more drowsy or dizzy; avoid alcoholic drinks for at least 24 hours after you receive methoxyflurane.

What side effects may I notice from using methoxyflurane?

During your surgery or procedure the anesthesiologist will closely monitory all your body systems and treat any serious side effects. Side effects that you should report to your prescriber or health care professional as soon as possible:

  • hallucinations

  • high body temperature

  • irregular heartbeat

  • lightheadedness or fainting spells

  • slow or difficult breathing

  • yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your prescriber or health care professional if they continue or are bothersome):

  • drowsiness, dizziness

  • headache

  • muscle weakness

  • nausea, vomiting

  • shivering

  • trembling

Where can I keep my medicine?

This does not apply as you only received general anesthetics in a hospital or clinic setting.


March 21, 2017


U.S. FDA-approved Package Insert