Antifreeze (ethylene glycol) poisoning in cats
Antifreeze is extremely toxic to cats. It contains the chemical ethylene glycol and is found in radiator coolant, motor oils, hydraulic brake fluid, paints, solvents and photography developing solutions. As little as one teaspoon can be fatal to a cat and the sweet taste of the formulation makes it very dangerous.
This article was written by a FirstVet vet
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Symptoms of antifreeze poisoning
- Behaviour similar to alcohol intoxication
- Excessive drinking or urination
- Sedation or depression
- Halitosis (bad breath)
- Lethargy and tiredness
- Lack of appetite
- Acute kidney failure
The symptoms occur in 3 stages as the poisoning progresses:
Stage 1 - 30 minutes to 12 hours after ingestion: signs are similar to alcohol poisoning (vomiting, incoordination, drooling, excessive drinking and urination, seizures).
Stages 2 and 3 - 12 to 24 hours after ingestion: initially the cat seems to improve but damage to internal organs is occurring. Within 24 hours the cat will show signs of severe kidney failure. Visible of signs of this are a lack of appetite, lethargy, drooling, bad breath, depression, vomiting, seizures and coma.
What you can do yourself
TVM UK, an animal health company, have developed an easy-to-remember acronym - S.P.E.E.D - to help owners if they think that their cat has eaten or drunk something poisonous. Your vet only has a short time frame to try to minimise the absorption of the poison so an immediate appointment is essential and potentially life-saving.
S - Stop access to any poison. It may seem obvious but stop your cat eating or drinking any more of the substance.
P - Phone the vet. Keep your vet’s phone number and their emergency (out of hours) number handy in case you ever need them.
E - Emergency appointment. You cannot ‘wait and see’ with poisons. Many do not affect your pet straight away. Some can take several days to show symptoms whilst there is ongoing damage to the internal organs. Getting your pet seen immediately gives them the best chance of effective treatment.
E - Evidence - Knowing what the potential poison is will really help your vet to make a rapid diagnosis and create the best treatment protocol for a successful recovery. If you have a label of the substance then take it with you. If you don’t have a label but have access to the substance then bring a sample to the vet for testing (only if it is safe to do so and you are not putting yourself or anyone else in danger). If you don’t have a label or a sample but your cat has been sick, then bring a sample of this with you (if safe to do so) as the ingredient may be present in the vomit. If you don’t have access to any of these then don’t worry as your pet’s blood can be tested via certain laboratories.
D - Don’t delay. Never wait because it could be too late. Act straight away!
Treatment of antifreeze poisoning
A prompt appointment is essential and potentially life-saving. Treatment focuses on preventing kidney damage. Do not try to make your cat sick at home as this may cause harm and will delay treatment. Once the vet has induced your cat to be sick, activated charcoal is given orally to prevent further absorption of the toxin from the stomach and intestines. A specific antidote, ethanol or 4-methylpyrazole, will be given. Intravenous fluid therapy is administered together with drugs to encourage urine output in order to reduce the risk of kidney damage. Blood tests will be done to monitor kidney function.
When to see your physical veterinarian
- If you think your cat has eaten antifreeze, or you notice any signs of poisoning, then contact your veterinarian immediately and make an emergency appointment.
- Visit TVM UK for more information on antifreeze poisoning and other common pet poisons.
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