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Generic name: Methoxyflurane
Drug class: General anesthetics

Medically reviewed by Last updated on Dec 27, 2021.


  • This medicine can cause long-term kidney problems when given at high doses. Rarely, liver problems have also happened with methoxyflurane. If you have questions, talk with your doctor.

Uses of Methoxyflurane:

  • It is used to ease pain.

What do I need to tell my doctor BEFORE I take Methoxyflurane?

For all patients taking methoxyflurane:

  • If you are allergic to methoxyflurane; any part of methoxyflurane; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you have any of these health problems: Blood pressure problems, breathing problems, heart disease, or kidney disease.
  • If you are very sleepy.
  • If you have had a recent head injury.
  • If you have recently drunk a lot of alcohol or taken a big amount of drugs that may slow your actions like phenobarbital or some pain drugs like oxycodone.
  • If you or a family member have had malignant hyperthermia after getting an anesthetic. Signs of this health problem include a very high fever, a fast heartbeat, muscle stiffness, and trouble breathing.
  • If you have had liver problems after getting an anesthetic.
  • If you are taking any of these drugs: Isoniazid, phenobarbital, or rifampicin.
  • If you are taking any drugs that can raise the chance of kidney problems. There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
  • If you are pregnant or in labor.


  • If the patient is a child. Do not give methoxyflurane to a child.

This is not a list of all drugs or health problems that interact with methoxyflurane.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take methoxyflurane with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Methoxyflurane?

  • Tell all of your health care providers that you take methoxyflurane. This includes your doctors, nurses, pharmacists, and dentists.
  • This medicine may be abused. It may be habit-forming.
  • Avoid driving and doing other tasks or actions that call for you to be alert until the effects of methoxyflurane wear off and you feel fully awake.
  • Avoid alcohol or other drugs and natural products that slow your actions.
  • If you are 65 or older, use methoxyflurane with care. You could have more side effects.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

How is this medicine (Methoxyflurane) best taken?

Use methoxyflurane as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • For breathing in only by an inhaler into the lungs.
  • You will be shown how to use methoxyflurane right before you take it.
  • Only use the device that comes with methoxyflurane. Do not use any other devices.
  • Do not use more than what your doctor told you to use. Do not use more often or longer than what you were told. Doing any of these things may raise the chance of very bad side effects.

What do I do if I miss a dose?

  • This medicine is given on an as needed basis.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of kidney problems like unable to pass urine, change in how much urine is passed, blood in the urine, or a big weight gain.
  • Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
  • Very bad dizziness or passing out.
  • Slow heartbeat.
  • Mood changes.
  • Memory problems or loss.
  • Not able to focus.
  • This medicine may cause a very bad and sometimes deadly problem called malignant hyperthermia. Call your doctor right away if you have a fast heartbeat, fast breathing, fever, or spasm or stiffness of the jaw muscles.

What are some other side effects of Methoxyflurane?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Dizziness.
  • Headache.
  • Feeling sleepy.
  • Upset stomach.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Methoxyflurane?

  • This medicine will be given in a hospital or doctor's office. You will not store it at home.

Consumer information use

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.