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

My 5 kg cat ate two brine-cured olives from the table, but my other cat didn't — do I need to worry about both?

Cats · Food safety

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

Short answer

You only need to monitor the cat that ate the olives. The main risk from brine-cured olives is the high salt content, which can cause increased thirst, vomiting, or diarrhea in sensitive individuals. Rinse any future olives thoroughly to remove excess salt. For the cat that ate them, offer fresh water and watch for those signs over the next 24 hours. If the other cat shows any odd behavior, a separate vet check is wise.

Olives — Food safety facts

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

Pitted, plain olives occasionally. Brine-cured olives are very salty — rinse first.

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

Olives 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

A heavy salt load drives up thirst and urination, and in the worst cases leads to sodium ion poisoning, which is a genuine emergency.

Stone-fruit pits and some seeds release cyanide when crushed, and quite apart from that they are a choking and blockage hazard.

Olives 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 Olives food facts page.

Open the full food page: Olives food facts →