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

My cat ate a few used hops from the fermenter yesterday, and the vet gave him fluids. What happens now?

Cats · Food safety

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

Short answer

The vet will keep him for observation until his temperature is stable. They're watching for a sudden dangerous fever, which can hit even hours after eating hops. You'll likely need to check his temperature at home for the next day or two—use a rectal thermometer if you can. If he seems restless, pants, or his gums feel hot, call the vet or the ASPCA poison line at 888-426-4435 immediately. Recovery looks normal once he's been fever-free for 48 hours.

Hops (used hops) — Food safety facts

Do not feed · Cats · full breakdown on the linked food page

Toxic — can trigger malignant hyperthermia (rapid, fatal rise in body temperature). Emergency if eaten.

Dogs and cats carry the same rating (Do not feed), so the notes below hold for either pet.

Hops (used hops) should not be given to cats at all. Even a small amount can do harm, so there is no portion small enough to be safe.

Do not induce vomiting and do not give milk or oil to “dilute” it. Note the food and roughly how much was eaten, then call your vet or a pet poison hotline and follow their advice on whether to bring the pet in straight away.

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.

Hops (used hops) has no place in everyday feeding: keep the rest of the day's food unchanged after this 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 Hops (used hops) food facts page.

Open the full food page: Hops (used hops) food facts →