When to see a vet urgently
Suspected exposure alone is enough to require immediate contact and emergency assessment, particularly in the following situations:
- Your cat has licked suspected coolant or it has got onto the coat.
- Your cat staggers, seems drunk or vomits after possible exposure.
- Breathing becomes difficult, your cat has seizures or collapses.
- Your cat passes unusually little or no urine and is unwell.
Contact a clinic immediately and leave without delay as instructed. You can find an emergency vet near you. Having no symptoms does not provide a safe period for monitoring at home.
Overview
Ethylene glycol is found in engine coolants, antifreeze fluids and some solvents. Cats cannot taste sweetness, so poisoning is usually accidental: a cat licks a coolant puddle or grooms fluid from its coat and paws. In a cat's body, the substance is rapidly metabolised into toxic compounds, glycolic acid and oxalic acid, that damage the kidneys and nervous system. Poisoning progresses quickly and needs immediate treatment.
Products with a similar purpose do not necessarily have the same composition. Not every antifreeze product contains ethylene glycol, and concentrations vary. Your vet therefore needs the most precise packaging information available. Do not identify an unknown technical fluid by tasting it, or infer that your cat's exposure is harmless from the product's colour.
Causes
The main cause is swallowing a fluid containing ethylene glycol. Routes of exposure include:
- directly drinking or licking coolant
- licking contaminated paws or fur
- access to maintenance areas or a garage
Poisoning does not require a cat to be visibly drinking from a bowl. A small leak along its route can contaminate paws, and grooming then carries the substance into the mouth. Rainwater collected in an old, apparently empty container can also contain residues. A dangerous exposure may therefore go completely unnoticed.
What to do before the appointment
Move your cat away from the substance and prevent further exposure. Tell the clinic immediately about suspected ethylene glycol, the possible exposure time, the product and any symptoms observed. Bring the packaging, a photograph of the label or a safely sealed sample if this can be done without delaying departure.
Do not induce vomiting or give home remedies or human medicines. Making an animal that is staggering or has altered consciousness vomit can allow material into the airways. An alcoholic drink is not an antidote to give at home. Ethanol treatment used by a vet is a monitored medical treatment.
If fluid is on the coat, tell the clinic immediately. Preventing licking and safe cleaning are planned according to your cat's condition. Do not delay transport of a weak cat or one with neurological signs for a lengthy bath at home. The skin and coat can be cleaned at the clinic as part of ending exposure.
Risk factors
The greatest risk is in cats that:
- have access outdoors or to a garage
- live near vehicles and sources of coolant
Exposure risk is primarily related to access to the substance. An indoor cat can also be endangered by a leaking container or splashes from maintenance work. Antifreeze products are used beyond car engines, so fluids in stores and technical equipment are checked according to their use and composition.
Symptoms
The clinical picture progresses through three stages:
Neurological stage, 0.5–12 hours:
- unsteady walking and impaired coordination
- drowsiness and depression
- vomiting and drooling
- seizures
Cardiorespiratory stage, 12–24 hours:
- faster breathing
- tachycardia, or a fast heart rate
- weakness and dehydration
Kidney disease stage, 24–72 hours:
- no urine or very little urine
- marked thirst but loss of appetite
- vomiting and diarrhoea
- severe lethargy and coma
The stages and times are only a guide. In cats, kidney damage and reduced urine production can develop within the first day. Not every stage is noticed, and you must not wait for respiratory or kidney signs before seeking help.
Early drunken behaviour may seem to improve for a while even as toxic breakdown products continue acting. Do not interpret this temporary improvement as recovery. Urine output may initially be higher than usual and later very low, so the clinical picture can also change considerably.
Complications and consequences
Ethylene glycol poisoning almost always leads to:
- acute kidney failure
- severe neurological disorders
- metabolic acidosis
- death without immediate treatment
This list describes possible consequences of severe untreated poisoning. However, treatment started very early can allow recovery, so death is not inevitable after every exposure. The prognosis becomes substantially worse once kidney damage has developed.
Important: even a teaspoonful of coolant is fatal to a cat. An antidote, fomepizole or ethanol under veterinary supervision, helps only within approximately the first 3 hours after poisoning. Go to a clinic at the slightest suspicion without waiting for symptoms.
The amounts and early antidote treatment window stated are not safety thresholds. Fluid concentration and the amount swallowed may be unknown, and you should not calculate whether exposure was below a lethal amount. Even if time has already passed, contact an emergency vet immediately. Your vet assesses the remaining treatment options.
Diagnosis at the vet
The following are used to confirm poisoning:
- the history, including possible access to coolant
- blood biochemistry showing raised creatinine and urea, hyperkalaemia and acidosis
- urine examination for calcium oxalate crystals
- rapid ethylene glycol tests, which are not always available
- kidney ultrasound to look for swelling and increased echogenicity
Diagnosis may rely on the combination of suspected exposure and findings because ingestion is often not witnessed. As well as kidney values, blood tests assess acid–base balance and electrolytes. Poisoning can cause changes before severe kidney failure is established.
The test method and time since exposure affect interpretation of an ethylene glycol test. The substance rapidly changes into other compounds, so looking only for the original substance later does not describe the whole injury. If a reliable confirmatory test is not available quickly, treatment may need to start on reasonable suspicion.
Calcium oxalate crystals in urine can support suspicion and indicate a serious situation, but the result is considered alongside other observations. Ultrasound helps assess the kidneys and other possible obstructions to urine output. Blood and urine changes may need repeated monitoring because the situation develops rapidly.
Antidote treatment and hospital care
Antidotes aim to prevent ethylene glycol from becoming toxic breakdown products. They are therefore most useful very early. Your vet selects a medicine and approach suitable for your cat. An antidote alone does not repair kidney damage that has already occurred, so later-stage treatment also addresses disturbances in the body.
A patient may need intravenous fluids, correction of acidity and electrolytes, and nausea treatment. Fluid volume is tailored to hydration and urine output. If the kidneys cannot remove fluid, uncontrolled administration of large amounts can be dangerous. Treatment therefore cannot be replaced by forcing water into your cat at home.
In hospital, fluid intake and output, weight, blood values and urine production can be monitored. A lack of urine does not mean more water automatically resolves the problem. Some seriously ill patients may need assessment for kidney replacement therapy, or dialysis, at a specialist centre if ordinary treatment cannot control the consequences.
Dialysis cleans the blood and helps correct some dangerous metabolic disturbances while the possibility of kidney recovery is assessed. It does not guarantee restoration of damaged tissue. Your vet assesses suitability, availability and the patient's overall prognosis.
Prognosis and follow-up
The prognosis depends particularly on when treatment starts, the severity of kidney damage and whether the cat produces urine. Eating, nausea and nutritional needs are also assessed. Follow-up of a recovering cat may require repeat blood and urine tests and individual feeding instructions.
After discharge, report new vomiting, failure to eat, marked weakness or a change in urine output to the clinic. Do not alter prescribed treatments or give medicines that may affect the kidneys on your own initiative. Acute kidney injury differs from chronic kidney disease developing over a long period, and monitoring is planned according to the injury that occurred.
Prevention
The risk of poisoning can only be reduced by preventing cats from accessing ethylene glycol:
- keep coolant and technical fluids out of cats' reach
- clean up any spills immediately
- prevent access to garages and storage areas
- use alternative coolants containing propylene glycol, which is less toxic
Less toxic does not mean safe to drink. Alternative technical fluids must also be kept out of reach. Check product ingredients and safety separately; a claim of being pet-friendly does not replace careful storage and removal of leaks.
Use labelled, closable containers and dispose of old fluids appropriately. Do not leave emptied packaging or containers outside to collect water. Check vehicles for leaks and clean up spills completely. Adding a bittering agent to a product also does not guarantee that an animal will not lick it.
What it means for owners
Ethylene glycol poisoning is one of the most serious forms of poisoning in cats. Remember that even a very small amount can be fatal. If you suspect your cat may have drunk coolant, take it to a vet immediately: every minute matters.
Note: this material provides general information and does not replace veterinary advice. Contact a vet immediately if symptoms appear.
Frequently asked questions
Can I wait for symptoms if my cat licked antifreeze?
No. Contact an emergency vet immediately about suspected exposure even in a cat without symptoms. Treatment works best before toxic breakdown products cause damage.
Is a brief improvement a sign of recovery?
Not necessarily. Early symptoms can improve while kidney damage progresses. Do not stop treatment or cancel an emergency visit on this basis.
Can I give alcohol as an antidote?
Do not give alcoholic drinks to your cat. Any ethanol treatment is carried out under veterinary supervision and requires administration and monitoring suited to the patient's situation.
Is a fluid containing propylene glycol safe?
It is not considered something a cat can drink. Even an alternative less toxic than ethylene glycol must be stored out of animals' reach, and any exposure is assessed from the exact product details.
This article is for general information only and is not a guide to treatment. If you notice the first signs of illness, contact your vet.
Paw4care editorial team
Sources
- Ethylene Glycol Toxicosis in Animals, Merck Veterinary Manual, accessed 2026-11-03.
- Ethylene Glycol Poisoning in Cats, VCA Animal Hospitals, accessed 2026-11-03.
- Antifreeze poisoning in cats, PDSA, accessed 2026-11-03.
- Cat poisoning: symptoms and how to spot it, Cats Protection, accessed 2026-11-03.
- Acute Kidney Injury in Cats, VCA Animal Hospitals, accessed 2026-11-03.
- Renal Dysfunction in Dogs and Cats, Merck Veterinary Manual, accessed 2026-11-03.
- Antifreeze, Pet Poison Helpline, accessed 2026-11-03.