Item Number: ALFAXAN
Alfaxan 10mg/ml solution for injection for dogs and cats.
Dogs and cats
Indications for use, specifying the target species:
As an induction agent prior to inhalation anaesthesia. As a sole anaesthetic agent for the induction and maintenance of anaesthesia for the performance of examination or surgical procedures.
Do not use in combination with other intravenous anaesthetic agents.
During recovery, it is preferable that animals are not handled or disturbed. This may lead to paddling,
minor muscle twitching or movements that are more violent.,While better avoided, such reactions are
Special precautions for use:
(i) Special precautions for use in animals
Appropriate analgesia should be provided in cases where procedures are anticipated to be painful
The safety of Alfaxan in animals less than 12 weeks of age has not been demonstrated.
Transient post induction apnoea frequently occurs, particularly in dogs – see section 4.6 for details. In
such cases, endotracheal intubation and oxygen supplementation should be employed. Facilities for
intermittent positive pressure ventilation should be available.
In order to minimise the possibility of apnoea, administer Alfaxan by slow intravenous injection and not as
a rapid dose.
Especially when using higher doses of Alfaxan, a dose-dependent respiratory depression may occur.
Oxygen and/or intermittent positive pressure ventilation should be administered to counteract the
threatening hypoxaemia/hypercapnea. This should be particularly important in risky anaesthetic cases
and whenever the anaesthesia is to be carried out for a longer period of time.
In both dogs and cats, the dose interval for maintenance of anaesthesia by intermittent bolus
administration may require lengthening by more than 20%, or the maintenance dose by intravenous
infusion may require reduction by more than 20%, when hepatic blood flow is severely diminished or
hepatocellular injury is severe. Revised: 29 April 2009
As with all general anaesthetic agents:
• It is advisable to ensure that the patient has been fasted before receiving the anaesthetic.
• Additional monitoring is advised and particular attention should be paid to respiratory parameters
parameters in aged animals, or in cases where there may be additional physiological stress
imposed by pre-existing pathology, shock or caesarean section.
• Following induction of anaesthesia, the use of an endotracheal tube is recommended to maintain
• It is advisable to administer supplemental oxygen during maintenance of anaesthesia.
• Respiratory embarrassment may occur – ventilation of the lungs with oxygen should be considered
if haemoglobin saturation with oxygen (SpO2%) falls below 90% or if apnoea persists for longer
than 60 seconds.
• If cardiac arrhythmias are detected, attention to respiratory ventilation with oxygen is the first
priority followed by appropriate cardiac therapy or intervention.
Psychomotor excitement may be encountered in a minority of dogs and cats recovering from Alfaxan
anaesthesia. Post-anaesthetic recovery should thus take place in appropriate facilities and under
sufficient supervision. Use of a benzodiazepine as the sole premedicant may increase the probability of
(ii) Special precautions to be taken by the person administering the veterinary medicinal product
If the product comes into contact with the eyes or skin, wash off immediately with water. In case of
accidental self injection seek immediate medical attention and show the product literature to the doctor.
Adverse reactions (frequency and seriousness):
In clinical studies using Alfaxan, 44% of dogs and 19% of cats experienced post induction apnoea, which
was defined as the cessation of breathing for 30 seconds or more. The mean duration of apnoea in these
animals was 100 seconds in dogs and 60 seconds in cats. Endotracheal intubation and oxygen
supplementation should therefore be employed.
Use during pregnancy, lactation or lay:
The safety of the veterinary medicinal product has not been established in cases where pregnancy is to be continued or during lactation. Its effects upon fertility have not been evaluated. However, studies using alfaxalone in pregnant mice, rats and rabbits have demonstrated no deleterious effects on gestation of the treated animals, or on the reproductive performance of their offspring. The product should be used in pregnant animals according to the risk-benefit assessment performed by the veterinarian.
Interaction with other medicinal products and other forms of interaction:
Alfaxan has been demonstrated to be safe when used in combination with the following premedicant classes:
Drug Class Examples Phenothiazines acepromazine maleate Anticholinergic agents atropine sulfate Benzodiazepines diazepam, midazolam hydrochloride, Alpha-2-adrenoceptor agonists xylazine hydrochloride, medetomidine hydrochloride Opiates methadone, morphine sulfate, butorphanol tartrate, buprenorphine hydrochloride NSAIDs carprofen, meloxicam.
The concomitant use of other CNS depressants should be expected to potentiate the depressant effects of Alfaxan, necessitating cessation of further administration of Alfaxan when the required depth of anaesthesia has been reached.
The use of one premedicant or a combination of premedicants often reduces the dose of Alfaxan required.
Premedication with alpha-2-adrenoceptor agonists such as xylazine and medetomidine can markedlyincrease the duration of anaesthesia in a dose dependent fashion. In order to shorten recovery periods it may be desirable to reverse the actions of these premedicants.
Benzodiazepines should not be used as sole premedicants in dogs and cats as the quality of anaesthesia in some patients may be sub-optimal. Benzodiazepines may be used safely and effectively in combination with other premedicants and Alfaxan.
Amounts to be administered and administration route:
Induction of anaesthesia:
The induction dose of Alfaxan is based on data taken from controlled laboratory and field studies and is the amount of drug required for 9 of 10 dogs or cats (i.e. 90th percentile) to be successfully induced for anaesthesia.
Dosing recommendations for induction of anaesthesia are as follows:
mg/kg 3 2 5 5
ml/kg 0.3 0.2 0.5 0.5
The dosing syringe should be prepared to contain the above dose. The rate of intravenous injection should be such that the total dose, if required, would be administered over the first 60 seconds. If, 60 seconds after complete delivery of this first induction dose, intubation is still not possible, one further similar dose may be administered to effect. The necessary injection rate can be achieved by administration of one quarter (¼) of the calculated dose every 15 seconds. Administration should continue until the clinician is satisfied that the depth of anaesthesia is sufficient for endotracheal intubation, or until the entire dose has been administered.
Maintenance of anaesthesia:
Following induction of anaesthesia with Alfaxan, the animal may be intubated and maintained on Alfaxan or an inhalation anaesthetic agent. Maintenance doses of Alfaxan may be given as supplemental boluses or as constant rate infusion. Alfaxan has been used safely and effectively in both dogs and cats for procedures lasting for up to one hour. The following doses suggested for maintenance of anaesthesia are based on data taken from controlled laboratory and field studies and represent the average amount of drug required to provide maintenance anaesthesia for a dog or cat. However the actual dose will be based on the response of the individual patient.
Alfaxan doses suggested for maintenance of anaesthesia are as follows:
Dose for constant rate infusion
mg/kg/hour 8 - 9 6 - 7 10 - 11 7 - 8
mg/kg/minute 0.13 - 0.15 0.10 - 0.12 0.16 - 0.18 0.11 - 0.13
ml/kg/minute 0.013 - 0.015 0.010 - 0.012 0.016 - 0.018 0.011 - 0.013
Bolus dose for each 10 minutes maintenance
mg/kg 1.3 - 1.5 1.0 - 1.2 1.6 - 1.8 1.1 - 1.3
ml/kg 0.13 - 0.15 0.10 - 0.12 0.16 - 0.18 0.11 - 0.13
Where maintenance of anaesthesia is with Alfaxan for procedures lasting more than 5 to 10 minutes, a butterfly needle or catheter can be left in the vein, and small amounts of Alfaxan injected subsequently to maintain the required level and duration of anaesthesia. In most cases the average duration of recovery when using Alfaxan for maintenance will be longer than if using an inhalant gas as a maintenance agent.
Overdose (symptoms, emergency procedures, antidotes), if necessary:
Acute tolerance to overdose has been demonstrated up to 10 times the recommended dose of 2 mg/kg in the dog (i.e. up to 20 mg/kg) and up to 5 times the recommended dose of 5 mg/kg in the cat (i.e. up to 25 mg/kg). For both dogs and cats, these excessive doses delivered over 60 seconds cause apnoea and a temporary decrease in mean arterial blood pressure. The decrease in blood pressure is not life threatening and is compensated for by changes in heart rate. These animals can be treated solely by intermittent positive pressure ventilation (if required) with either room air or, preferably, oxygen. Recovery is rapid with no residual effects.
In the absence of compatibility studies, the veterinary medicinal product must not be mixed with other
veterinary medicinal products.
Shelf life of the veterinary medicinal product as packaged for sale: 30 months.
This product does not contain an antimicrobial preservative. Any solution remaining in the vial following
withdrawal of the required dose should be discarded.
Special precautions for storage:
Do not freeze. Keep the container in the outer carton.
Nature and composition of immediate packaging:
Cardboard box with one glass vial of 10 ml with a bromobutyl rubber stopper and aluminium cap.
Special precautions for the disposal of unused veterinary medicinal product or waste materials:
derived from the use of such products
Any unused product or waste materials should be disposed of in accordance with national requirements.
ALFAXAN: Data Sheet