isoflurane at a glance
Class
Halogenated volatile general anaesthetic
Licensed role
Induction and maintenance of general anaesthesia
Administration
Inhaled through an anaesthetic breathing system using a calibrated vaporiser
Supervision
Given by appropriately trained professionals in an equipped clinical setting
What is isoflurane used for?
The selected product is licensed as a general inhalation anaesthetic.
Starting general anaesthesia
Maintaining general anaesthesia during surgery or another procedure
How does isoflurane work?
Isoflurane affects several ion channels in the brain and spinal cord. It enhances inhibitory signalling and reduces excitatory nerve activity, producing unconsciousness, amnesia and immobility. No single target fully explains general anaesthesia.
How to take isoflurane
Isoflurane is not self-administered. An anaesthetist delivers its vapour through a mask or breathing tube and adjusts it using a calibrated vaporiser. Follow the hospital’s instructions about fasting and regular medicines.
Tell the team about all medicines, allergies and previous reactions to anaesthesia.
Mention any family history of malignant hyperthermia or unexplained serious problems during anaesthesia.
Arrange the recommended support and transport for recovery.
isoflurane side effects
Common or expected effects
- Feeling or being sick
- Shivering or chills
- Drowsiness, confusion or temporary memory problems
- Agitation or delirium during recovery
- Sore throat or hoarse voice related to airway equipment
Get urgent medical advice
- Malignant hyperthermia, potentially involving muscle rigidity, rapidly rising temperature, fast heartbeat and unstable blood pressure
- Severe allergic reaction, including breathing difficulty, wheezing or facial swelling
- Marked breathing depression or bronchospasm
- Abnormal heart rhythm, including QT-related arrhythmia
- Severe potassium elevation, particularly in susceptible children or people with neuromuscular disease
- Liver injury, which is very rare but can be severe
isoflurane in pregnancy
Pregnancy information is limited, so specialists should assess the benefits and risks. Isoflurane can relax the uterus and may increase uterine bleeding, although the product is licensed for maintaining anaesthesia during caesarean section.
isoflurane while breastfeeding
It is not established whether isoflurane or its metabolites enter human milk. Tell the anaesthetic team that you are breastfeeding. UK perioperative guidance generally supports resuming once you are awake and able to hold and feed the baby safely; advice may differ for premature or medically vulnerable infants or because of other medicines used.
isoflurane interactions
The anaesthetic team should review all prescribed, non-prescribed and recreational substances beforehand.
Adrenaline, noradrenaline and other sympathomimetics
May increase the risk of ventricular arrhythmia or perioperative hypertension.
Non-selective monoamine oxidase inhibitors
May increase the risk of a serious perioperative cardiovascular reaction and require advance specialist planning.
Calcium-channel blockers
Can add to myocardial depression and cause marked hypotension.
Common questions about isoflurane
Answers are fully visible for fast scanning and source review.
Is isoflurane a liquid or a gas?
It is stored as a volatile liquid and converted into vapour for inhalation by a calibrated vaporiser.
Who can give isoflurane?
Trained anaesthesia professionals in a suitably equipped clinical environment.
Can isoflurane cause malignant hyperthermia?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.