Volatile Inhalational Anaesthetic Pregnancy: No adequate and well-controlled studies in pregnant women; use during pregnancy only if clearly needed. Has a relaxant effect on the uterus. Advise women to skip breast-feeding for 48 hours after administration and discard milk produced during this period (§4.6).

Sevoflurane

Brand names: Ultane, Sevorane

Sevoflurane is a volatile halogenated inhalational anaesthetic agent used for the induction and maintenance of general anaesthesia in adults and children.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Induction: inspired concentrations up to 5% usually produce surgical anaesthesia in under 2 minutes (up to 8% may be used for induction in unpremedicated patients). Maintenance: surgical anaesthesia sustained with 0.5–3% sevoflurane, with or without concomitant nitrous oxide

Route: Inhalation, via a vaporiser specifically calibrated for sevoflurane

Frequency: Continuous during anaesthesia; individualised and titrated to effect

SPC (Sevoflurane). MAC values decrease with age and with the addition of nitrous oxide — average MAC in oxygen approximately 2.6% at age 25, 2.1% at 40, 1.7% at 60, 1.4% at 80; the concentration to achieve MAC in an 80-year-old is approximately 50% of that required in a 20-year-old. Paediatric: induction inspired concentrations up to 7% usually produce surgical anaesthesia in under 2 minutes; MAC in oxygen is age-dependent (0–1 months 3.3%, 1–6 months 3.0%, 6 months–3 years 2.8%, 3–12 years 2.5%); MAC in premature infants not determined. To be administered only by persons trained in general anaesthesia.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Known or suspected sensitivity to sevoflurane or other halogenated anaesthetics (e.g. history of liver function disorder, fever or leucocytosis of unknown cause after anaesthesia with one of these agents)
Known or suspected genetic susceptibility to malignant hyperthermia
Patients in whom general anaesthesia is contraindicated

Side effects

Hypotension (very common)
Nausea (very common)
Vomiting (very common)
Agitation (very common)
Bradycardia (very common)

Interactions

Succinylcholine — associated with perioperative hyperkalaemia that has resulted in cardiac arrhythmias and death in paediatric patients (§4.4)

Clinical monograph

How it works

It produces general anaesthesia through actions on central nervous system ligand-gated ion channels, including potentiation of GABA-A receptor activity, leading to loss of consciousness.

Prescribing in practice

It is a recognised trigger of malignant hyperthermia in susceptible individuals, so a personal or family history must be sought and dantrolene and an emergency protocol must be available.
Its low pungency and rapid onset and offset make it well suited to inhalational (gas) induction, particularly in paediatric anaesthesia.
It causes dose-dependent respiratory and cardiovascular depression and must be delivered through a calibrated vaporiser with anaesthetic gas scavenging.

Monitoring

Monitor end-tidal anaesthetic concentration, oxygenation, ventilation, haemodynamics and temperature throughout administration.

Counselling the patient

This anaesthetic gas is delivered by an anaesthetist with full monitoring.
Tell the team about any personal or family history of serious reactions to anaesthesia.

Evidence & guidelines

Its use in induction and maintenance of anaesthesia, including paediatric gas induction, is standard practice supported by the SPC and anaesthetic guidance.

Reference: RCoA GPAS 2023; AAGBI Malignant Hyperthermia Guidelines 2020; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

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