- Chewed or swallowed = burns
- Quick
- Affects: Mouth & gut (chemical burns)
Why this verdict for dogs
Batteries are a double emergency: leaking alkaline causes chemical burns to the mouth and gut, and a swallowed battery can block the intestine. Button batteries are the worst.
Warning signs to watch for
- Drooling
- Mouth pain or burns
- Vomiting
- Not eating
⚠ If your dog ate batteries
Act immediately — don't wait for symptoms.
- Call your vet or a pet poison helpline right away.
- Note how much was eaten and when.
- Do not induce vomiting unless a professional tells you to.
Batteries are two very different emergencies wearing the same shape, and telling them apart matters enormously. A chewed AA is a chemical burn risk. A swallowed button or coin cell is one of the fastest-moving emergencies in this entire list, capable of doing serious damage in about two hours.
How much is safe?
Any battery is a problem, but a lithium button cell — the flat silver discs in remotes, key fobs, scales, hearing aids and light-up toys — is in a category of its own. It does not need to leak to cause harm: sitting against moist tissue, it generates its own electrical current, which destroys the lining of the oesophagus or stomach from the inside. Alkaline cylindrical batteries are dangerous mainly if punctured by teeth, releasing caustic material that burns the mouth and throat.
What happens if a dog eats too much?
With a chewed alkaline battery, look for drooling, pawing at the mouth, refusal to eat, mouth pain and ulcers on the tongue or gums. With a swallowed button cell the outward signs may be minimal at first, which is exactly what makes it dangerous — then come drooling, gagging, difficulty swallowing, vomiting and lethargy as the burn deepens. Metal casings can also cause zinc or heavy-metal toxicity if they sit in the stomach for days.
⚠ What to do if your dog ate batteries
Go to a veterinary hospital now — do not wait, and do not phone around for an appointment. Call from the car (ASPCA 888-426-4435 · Pet Poison Helpline 855-764-7661). Do not induce vomiting: a battery coming back up burns the oesophagus a second time. Do not offer food or water until a vet advises it. Take an identical battery with you if you can, so the team knows the exact type and voltage. Button cells often need to be removed by endoscopy urgently.
⚠️ Worried your pet got into this?
Frequently asked questions
How do I know if it was a button battery or an alkaline one?
Button cells are flat discs, usually a couple of centimetres across or smaller, and are found in remotes, key fobs, watches and light-up toys. If you are not certain which type is missing, treat it as a button cell and go in.
It has been a few hours and my dog seems fine — do I still go?
Yes. Button-cell injury develops under the surface and a normal-looking pet can already have a deep oesophageal burn.
More household items for dogs
By the CanMyPet Editorial Team · Reviewed against ASPCA Animal Poison Control, the American Kennel Club (AKC) and Pet Poison Helpline · Last updated July 31, 2026.
Sources
- ASPCA — People Foods to Avoid Feeding Your Pets
- American Kennel Club — Dog Nutrition
- Pet Poison Helpline — Poison List