Do not use in cases of known susceptibility to malignant hyperthermia.
Do not use in cases of hypersensitivity the active substance.
The ease and rapidity of alteration of the depth of anaesthesia with isoflurane and its low metabolism, may be considered advantageous for its use in special groups of patients such as the old or young, and those with impaired hepatic, renal or cardiac function.
Isoflurane has little or no analgesic properties. Adequate analgesia should always be given before surgery. The analgesic requirements of the patient should be reviewed again before the general anaesthesia has ended.
Isoflurane causes depression of the cardiovascular and respiratory systems.
It is important to monitor pulse quality and rate in all patients. The use of the product in patients with cardiac disease should only be considered after a benefit risk assessment by the responsible veterinary surgeon. In the case of cardiac arrest, complete cardio pulmonary resuscitation should be performed.
It is important to monitor respiratory rate and quality. It is also important to maintain an open airway and to properly oxygenate tissues during the maintenance of anaesthesia. Respiratory arrest should be treated by assisted ventilation.
The metabolism of isoflurane in birds and small mammals can be affected by decreases in body temperature that may occur secondary to a high surface area to bodyweight ratio. Therefore body temperature should be monitored and kept stable during treatment. Drug metabolism in reptiles is slow and highly dependent upon environmental temperature. Reptiles may be difficult to induce with inhalation agents due to breath holding.
Horses, dogs, cats, ornamental birds, reptiles, rats, mice, hamsters, chinchillas, gerbils, guinea pigs and ferrets:
Rare (1 to 10 animals / 10,000 animals treated) | bradycardia1, arrhythmias |
Very rare (<1 animal / 10,000 animals treated, including isolated reports) | cardia arrest, respiratory arrest, malignant hyperthermia2 |
Undetermined frequency | hypotension3, respiratory depression3 |
1 Transient.
2 Susceptible animals.
3 Dose-related
Isoflurane overdose may result in profound respiratory depression. Therefore, respiration must be monitored closely and supported when necessary with supplementary oxygen and/or assisted ventilation.
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 its local representative or the national competent authority via the national reporting system.
In cases of severe cardiopulmonary depression, administration of isoflurane should be discontinued, the breathing circuit should be flushed with oxygen, the existence of a patent airway ensured, and assisted or controlled ventilation with pure oxygen initiated. Cardiovascular depression should be treated with plasma expanders, pressor agents, antiarrhythmic agents or other appropriate techniques.
Pregnancy: Use only according to the benefit/risk assessment by the responsible veterinarian. Isoflurane has been safely used for anaesthesia during caesarean section in the dog and cat.
Lactation: Use only according to the benefit/risk assessment by the responsible veterinarian.
Withdrawal period
Horses (meat): 2 days. Not to be used for the treatment of mares producing milk for human consumption.
User warnings
Do not breathe the vapour. Users should consult their National Authority for advice on Occupational Exposure Standards for isoflurane.
Operating rooms and recovery areas should be provided with adequate ventilation or scavenging systems to prevent the accumulation of anaesthetic vapour. All scavenging/extraction systems must be adequately maintained.
Adverse effects on foetuses and pregnant animals were observed in laboratory animals. Pregnant and breast-feeding women should not have any contact with the product and should avoid operating rooms and animal recovery areas. Avoid using masking procedures for prolonged induction and maintenance of general anaesthesia.
Use cuffed endotracheal intubation when possible for the administration of IsoFlo during maintenance of general anaesthesia.
Care should be taken when dispensing isoflurane, with any spillage removed immediately using an inert and absorbent material e.g. sawdust. Wash any splashes from skin and eyes, and avoid contact with the mouth. If severe accidental exposure occurs remove the operator from the source of exposure, seek medical advice immediately and show the package leaflet or the label to the physician.
Halogenated anaesthetic agents may induce liver damage. In case of isoflurane this is an idiosyncratic response very rarely seen after repeated exposure.
To the physician: Ensure a patent airway and give symptomatic and supportive treatment. Note that adrenaline and catecholamines may cause cardiac dysrhythmias.