You must contact a veterinarian immediately. Do not try to treat the cat yourself. A veterinarian will be able to assess the situation and provide the appropriate treatment.
Here's what you can do:
* Call your local emergency veterinary clinic or animal poison control center. They can provide immediate advice and guidance.
* Transport the cat to the veterinary clinic as quickly as possible. Time is of the essence in cases of antifreeze poisoning.
* If possible, take the container of antifreeze with you to the clinic. This will help the veterinarian determine the type of antifreeze and the best course of treatment.
Please remember, a veterinarian is the best resource for treating a cat that has ingested antifreeze.