POM-V Prescription Required Companion Animal

Sevohale 100% v/v Inhalation Vapour, Liquid for Dogs and Cats

Active ingredient: Sevoflurane

Form

Inhalation vapour, liquid

Species

Cats Dogs

Manufacturer

Chanelle Pharmaceuticals Manufacturing Ltd

VMD MA No.

08749/5026

What it's used for

For the induction and maintenance of anaesthesia.

Full indications, dosage and side effects ↓

View official SPC (PDF)

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Paying less for Sevoflurane

1

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2

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Clinical information

Sevohale 100% v/v Inhalation Vapour, Liquid for Dogs and Cats — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 27 Mar 2026.

For the induction and maintenance of anaesthesia.

Inspired concentration:
This veterinary medicinal product should be administered via a vaporiser specifically
calibrated for use with sevoflurane so that the concentration delivered can be
accurately controlled. The veterinary medicinal product contains no stabiliser and
does not affect the calibration or operation of these vaporisers in any way. The
administration of sevoflurane must be individualised based on the dog's or cat’s
response.
Premedication:
The necessity for and choice of premedication is left to the discretion of the
veterinarian. Preanaesthetic doses for premedicants may be lower than the label
directions for their use as a single medication.
Induction of anaesthesia:
For mask induction using sevoflurane, inspired concentrations of 5 to 7%
sevoflurane with oxygen are employed to induce surgical anaesthesia in the healthy
dog, and 6 to 8% sevoflurane with oxygen in the cat. These concentrations can be
expected to produce surgical anaesthesia within 3 to 14 minutes in dogs and within 2
to 3 minutes in cats. Sevoflurane concentration for induction may be set initially, or
may be achieved gradually over the course of 1 to 2 minutes. The use of
premedicants does not affect the concentration of sevoflurane required for induction.
Maintenance of anaesthesia:
Sevoflurane may be used for maintenance anaesthesia following mask induction
with sevoflurane or following induction with injectable agents. The concentration of
sevoflurane necessary to maintain anaesthesia is less than that required for
induction.
Surgical levels of anaesthesia in the healthy dog may be maintained with inhaled
concentrations of 3.3 to 3.6% in the presence of premedication. In the absence of
premedication, inhaled concentrations of sevoflurane in the range 3.7 to 3.8% will
provide surgical levels of anaesthesia in the healthy dog.
In the cat surgical anaesthesia is maintained with sevoflurane concentrations of 3.7-
4.5%.
The presence of surgical stimulation may require an increase in the concentration of
sevoflurane.
The use of injectable induction agents without premedication has little effect on the
concentrations of sevoflurane required for maintenance.
Anaesthetic regimens that include opioid, alpha-2-agonist, benzodiazepine or
phenothiazine premedication will allow the use of lower sevoflurane maintenance
concentrations.

Do not use in cases of hypersensitivity to sevoflurane or other halogenated
anaesthetic agents.
Do not use in animals with a known or suspected genetic susceptibility to malignant
hyperthermia.

Very common
(>1 animal / 10 animals treated):
Hypotension
, tachypnoea, muscle
tenseness, excitation, apnoea, muscle
fasciculations, emesis.
Common
(1 to 10 animals / 100 animals treated):
Respiratory depression
, bradycardia
Very rare
(<1 animal / 10,000 animals treated,
including isolated reports):
Paddling, retching, salivation, cyanosis,
premature ventricular contractions,
excessive cardiopulmonary depression.
Undetermined frequency (cannot be
estimated from the available data)
Malignant hyperthermia
elevated
aspartate aminotransferase (AST)
5,6
,
elevated alanine aminotransferase
(ALT)
5,6
, elevated lactate
dehydrogenase (LDH)
5,7
, elevated
bilirubin
5,7
,
leucocytosis
5,7
may result in decreased renal blood flow.
dose-dependent respiratory depression is commonly observed while using
sevoflurane, therefore respiration should be closely monitored during sevoflurane
anaesthesia and the inspired concentration of sevoflurane adjusted accordingly.
may be reversed by administration of anticholinergics.
the possibility of sevoflurane triggering episodes of malignant hyperthermia in
susceptible dogs and cats cannot be ruled out.
transient.
in cats hepatic enzymes tend to remain within the normal range.
in dogs.
Reporting adverse events is important. It allows continuous safety monitoring of a
veterinary medicinal product. Reports should be sent, preferably via a veterinarian,
to either the marketing authorisation holder or the national competent authority via
the national reporting system. See also the package leaflet for respective contact
details.

None.

Special precautions for safe use in the target species:
Halogenated volatile anaesthetics can react with dry carbon dioxide (CO2)
absorbents to produce carbon monoxide (CO) that may result in elevated levels of
carboxyhaemoglobin in some dogs.
In order to minimise this reaction in rebreathing anaesthetic circuits, this veterinary
medicinal product should not be passed through soda lime or barium hydroxide that
has been allowed to dry out.
The exothermic reaction that occurs between inhalation agents (including
sevoflurane) and CO2 absorbents is increased when the CO2 absorbent becomes
desiccated, such as after an extended period of dry gas flow through the CO2
absorbent canisters. Rare cases of excessive heat production, smoke and/or fire in
the anaesthetic machine have been reported during the use of a desiccated CO2
absorbent and sevoflurane. An unusual decrease in the expected depth of
anaesthesia compared to the vaporiser setting may indicate excessive heating of the
CO2 absorbent canister.
If it is suspected that the CO2 absorbent may be desiccated, it must be replaced.
The colour indicator of most CO2 absorbents does not necessarily change as a
result of desiccation. Therefore, the lack of significant colour change should not be
taken as an assurance of adequate hydration. CO2 absorbents should be replaced
routinely regardless of the state of the colour indicator.
1,1,3,3,3-pentafluoro-2-(fluoromethoxy)propene (C4H2F6O), also known as
Compound A, is produced when sevoflurane interacts with soda lime or barium
hydroxide. Reaction with barium hydroxide results in a greater production of
Compound A than does the reaction with soda lime. Its concentration in a circle
absorber system increases with increasing sevoflurane concentrations and with
decreasing fresh gas flow rates. Sevoflurane degradation in soda lime has been
shown to increase with temperature. Since the reaction of carbon dioxide with
absorbents is exothermic, this temperature increase will be determined by the
quantities of CO2 absorbed, which in turn will depend on fresh gas flow in the
anaesthetic circle system, metabolic status of the dog and ventilation. Although
Compound A is a dose-dependent nephrotoxin in rats, the mechanism of this renal
toxicity is unknown. Long duration, low-flow sevoflurane anaesthesia should be
avoided due to the risks of Compound A accumulation.
During maintenance of anaesthesia, increasing the concentration of sevoflurane
produces a dose dependent decrease in blood pressure. Due to sevoflurane's low
solubility in blood, these haemodynamic changes may occur more rapidly than with
other volatile anaesthetics. Arterial blood pressure should be monitored at frequent
intervals during sevoflurane anaesthesia. Facilities for artificial ventilation, oxygen
enrichment and circulatory resuscitation should be immediately available. Excessive
decreases in blood pressure or respiratory depression may be related to the depth of
anaesthesia and may be corrected by decreasing the inspired concentration of
sevoflurane. The low solubility of sevoflurane also facilitates rapid elimination by the
lungs.
The nephrotoxic potential of certain NSAIDs, when used in the perioperative period,
may be exacerbated by hypotensive episodes during sevoflurane anaesthesia. In
order to maintain renal blood flow, prolonged episodes of hypotension (mean arterial
pressure below 60 mmHg) should be avoided in dogs and cats during sevoflurane
anaesthesia.
In common with all volatile agents, sevoflurane may cause hypotension in
hypovolaemic animals such as those requiring surgery to repair traumatic injury, and
lower doses should be administered in combination with appropriate analgesics.
Sevoflurane may trigger episodes of malignant hyperthermia in susceptible dogs and
cats. If malignant hyperthermia develops, the anaesthetic supply should be
interrupted immediately and 100% oxygen administered using fresh anaesthetic
hoses and a rebreathing bag. Appropriate treatment should readily be instituted.
Compromised or debilitated dogs and cats:
Doses of sevoflurane may need adjustment for geriatric or debilitated animals.
Doses required for maintenance of anaesthesia may need to be reduced by
approximately 0.5% in geriatric dogs (i.e. 2.8% to 3.1% in premedicated geriatric
dogs and 3.2 to 3.3% in unpremedicated geriatric dogs). There is no information on
the adjustment of the maintenance dose in cats. Adjustment is, therefore, left to the
discretion of the veterinarian. Limited clinical experience in administering sevoflurane
to animals with renal, hepatic and cardiovascular insufficiency suggests that
sevoflurane may be safely used in these conditions. However, it is recommended
that such animals be monitored carefully during sevoflurane anaesthesia.
Sevoflurane may cause a small increase in intracranial pressure (ICP) under
conditions of normocapnia in dogs. In dogs with head injuries or other conditions
placing them at risk from increased ICP, it is recommended that hypocapnia be
induced by means of controlled hyperventilation as a means of preventing changes
in ICP.
There are limited data to support the safety of sevoflurane in animals less than
12 weeks of age. Therefore, it should only be used in these animals according to a
benefit-risk assessment by the responsible veterinary surgeon.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
In order to minimise exposure to sevoflurane vapour, the following recommendations
are made:
• Use a cuffed endotracheal tube when possible for the administration of the
veterinary medicinal product during maintenance anaesthesia.
• Avoid using masking procedures for prolonged induction and maintenance of
general anaesthesia.
• Ensure that operating rooms and animal recovery areas are provided with
adequate ventilation or scavenging systems to prevent the accumulation of
anaesthetic vapour.
• All scavenging/extraction systems must be adequately maintained.
• Pregnant and breast-feeding women should not have any contact with the
product and should avoid operating rooms and animal recovery areas.
• Care should be taken when dispensing this veterinary medicinal product, with
immediate removal of any spillage.
• Do not inhale the vapour directly.
• Avoid contact by mouth.
• Halogenated anaesthetic agents may induce liver damage. This is an
idiosyncratic response very occasionally seen after repeated exposure.
• From an environmental point of view, it is considered good practice to use
charcoal filters with scavenging equipment.
Direct exposure to eyes may result in mild irritation. If eye exposure occurs, the eye
should be flushed with plenty of water for 15 minutes. Medical attention should be
sought if irritation persists.
In case of accidental contact with the skin, wash the affected area with abundant
water.
Symptoms of human overexposure (inhalation) to sevoflurane vapour include
respiratory depression, hypotension, bradycardia, shivering, nausea and headache.
If these symptoms occur, the individual should be removed from the source of
exposure and medical attention sought.
Advice to doctors: Maintain a patent airway and give symptomatic and supportive
treatment.
Special precautions for the protection of the environment:
Not applicable.

Intravenous anaesthetics:
Sevoflurane administration is compatible with the intravenous barbiturates and
propofol and in cats alfaxalone and ketamine. In dogs, the concurrent administration
of thiopental, however, may slightly increase sensitivity to adrenaline induced cardiac
arrhythmias.
Benzodiazepines and opioids:
Sevoflurane administration is compatible with the benzodiazepines and opioids
commonly used in veterinary practice. In common with other inhalational
anaesthetics, the MAC of sevoflurane is reduced by the concurrent administration of
benzodiazepines and opioids.
Phenothiazines and alpha-2-agonists:
Sevoflurane is compatible with phenothiazines and alpha-2-agonists commonly used
in veterinary practice. Αlpha-2-agonists have an anaesthetic sparing effect and
therefore the dose of sevoflurane should be reduced accordingly. Limited data are
available on the effects of the highly potent alpha-2- agonists (medetomidine,
romifidine and dexmedetomidine) as premedication. Therefore they should be used
with caution. Alpha-2-agonists cause bradycardia which may occur when they are
used with sevoflurane. Bradycardia can be reversed by the administration of
anticholinergics.
Anticholinergics:
Studies in dogs and cats show that anticholinergic premedication is compatible with
sevoflurane anaesthesia in dogs and cats.
In a laboratory study, the use of a acepromazine/oxymorphone/thiopental/sevoflurane
anaesthetic regimen resulted in prolonged recoveries in all the dogs treated, compared
to recoveries in dogs anaesthetised with sevoflurane alone.
The use of sevoflurane with nondepolarising muscle relaxants has not been
evaluated in dogs. In cats sevoflurane has been shown to exert some neuromuscular
blocking effect, but this is only apparent at high doses. In humans sevoflurane
increases both the intensity and duration of neuromuscular blockade induced by
nondepolarising muscle relaxants. Neuromuscular blocking agents have been used
in cats anaesthetised with sevoflurane without any unexpected effects.

Do not store above 25 C.
Do not refrigerate.
Keep the bottle tightly closed.

Not applicable.
4.

This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.