Suspect poisoning? US: ASPCA Poison Control (888) 426-4435 · UK: 01202 509 000 · Severe symptoms → nearest emergency vet now.

My 4 kg cat ate two bites of cooked eel that were left out on the counter overnight — should I worry about spoilage?

Cats · Food safety

Last reviewed: 2026-09-05 · Reference ranges: ASPCA, Pet Poison Helpline & Merck Veterinary Manual

Short answer

Yes, you should worry. Eel is very high in fat, which goes rancid quickly at room temperature and can cause pancreatitis or severe gastroenteritis. Spoiled eel may also harbor bacteria that lead to vomiting and diarrhea. Watch for signs like lethargy, abdominal pain, or refusing food over the next 24 hours. Offer plain water and a bland diet if she'll eat, but call your vet if she shows any discomfort — cooked eel should only be given fresh and in tiny amounts.

Eel — Food safety facts

Feed with care · Cats · full breakdown on the linked food page

Very high in fat, and raw eel blood is toxic. Cooked plain in tiny amounts only.

Dogs and cats carry the same rating (Feed with care), so the notes below hold for either pet.

Eel is not poisonous to cats, but it is easy to over-feed. Rich fat, salt or seasoning can bring on vomiting or diarrhoea within a day, and repeated large portions are a recognised trigger for pancreatitis.

If it ate some before you noticed, watch for vomiting, diarrhoea, loss of appetite, unusual tiredness or a painful, swollen abdomen over the next 24 hours. A one-off small amount in a healthy adult usually passes with water and rest; repeated exposure, a puppy or kitten, a senior, or a pet with an ongoing illness is a reason to call your vet the same day.

Why these cautions matter

Rich, fatty food is the classic trigger for pancreatitis, a painful inflammation of the pancreas that usually needs veterinary treatment rather than rest alone.

Raw animal protein carries Salmonella and E. coli risk, and those bacteria can spread to the people in the household too.

Eel can turn up now and then, but not as a daily habit: keep the rest of the day's food unchanged and watch the litter box and how quickly they finish the next meal.

The full verdict, portion guidance and serving notes are collected on the Eel food facts page.

Open the full food page: Eel food facts →