For animal treatment only.

The agent should not be used in animals with a known sensitivity to Isoflurane or other inhalational agents.

Levels of anaesthesia can be altered easily and rapidly with Isoflurane. Hence it is recommended that only vaporisers which are reliable and produce a predictable concentration of Isoflurane should be employed.

Isoflurane produces a dose-related depression of respiration and, with increasing depth of anaesthesia, both tidal volume and respiratory rate are decreased. This depression is partially reversed by surgical stimulation even at deep levels of anaesthesia. Respiratory activity should be monitored closely and assisted or controlled when necessary.

Administration of Isoflurane will also produce a dose-related depression of arterial blood pressure, although this is raised by surgical stimulation. Any excessive depression of the arterial blood pressure, unrelated to hypovolaemia, is normally related to the depth of anaesthesia. It can usually be corrected by reducing the administered concentration of Isoflurane although it may be necessary, in horses, to administer an inotropic agent such as dobutamine. However, the heart rate is normally stable and, by the use of controlled ventilation, the PaCO2 can be maintained within the normal range as can cardiac output. Spontaneous ventilation with Isoflurane anaesthesia can lead to hypercapnia with an accompanying increase in heart rate and cardiac output greater than that observed with controlled ventilation.

Isoflurane sensitises the myocardium to the dysrhythmogenic effects of circulating catecholamines in the dog but to a lesser extent than other halogenated anaesthetic agents.

Side effects include respiratory depression, hypotension and vasodilation.

Malignant hyperthermia with halogenated agents has been reported in horses and dogs.

Isoflurane anaesthesia is normally accompanied by muscle relaxation which may be adequate for most surgical procedures. However, if profound muscle relaxation is required to initiate intermittent positive pressure ventilation for thoracic surgery, muscle relaxants may be used. All of the commonly available non-depolarising muscle relaxants are potentiated by Isoflurane. Hence the duration of neuromuscular blockade will be longer than with most other anaesthetic techniques. Whilst the anticholinesterase drugs will reverse the non-depolarising neuromuscular block, they do not influence the neuromuscular depression produced by Isoflurane.

In the event of overdosage, cease Isoflurane administration, check the airway and, if an endotracheal tube is not in place, one should be inserted. Intermittent positive pressure ventilation with oxygen should be initiated.

When using Isoflurane to anaesthetise an animal with a head injury, consideration should be given as to whether artificial ventilation is appropriate to maintain normal CO2 levels, so that cerebral blood flow does not increase.

In cats, intubation may be assisted by use of lidocaine spray to avoid laryngospasm.

Not to be used in horses intended for human consumption.

Treated horses may never be slaughtered for human consumption.

The horse must have been declared as not intended for human consumption under national Horse Passport legislation.

Wash any splashes from skin and eyes immediately and avoid contact with the mouth.

Care should be taken when dispensing Isoflurane, with immediate removal of spillage using an inert and absorbent material e.g. sawdust.

Do not breathe vapour. Users should consult their relevant National Authority for advice on Occupational Exposure Standards for Isoflurane.

Pregnant and breast-feeding women should avoid exposure to the product. Operating rooms should have an adequate active extraction system, and induction/recovery areas should be well ventilated, in order to ensure that atmospheric concentrations of Isoflurane stay well below the OES. Use with efficient scavenging equipment.

All scavenging/extraction systems must be adequately maintained and anaesthetic equipment regularly checked for leaks.

Avoid using masking procedures for prolonged induction and maintenance of general anaesthesia. Use cuffed endotracheal intubation when possible for the administration of isoflurane during maintenance of general anaesthesia.

Although Isoflurane has a low potential for damage to the atmosphere, it is considered good practice to use charcoal filters with scavenging equipment.

In the event of severe acute accidental exposure remove the operator from the source of exposure, seek urgent medical assistance and show this label.

Halogenated anaesthetic agents may induce liver damage. In the case of isoflurane this is an idiosyncratic response very rarely seen after repeated exposure.

Maintain a patent airway and give symptomatic and supportive treatment. Doctors should be aware that the use of adrenaline and catecholamines is contraindicated since they may cause severe cardiac dysrhythmia.

Dispose of any unused product and empty containers in accordance with guidance from your local waste regulation authority.