- Caffeine — bags & strong tea worst
- 1–2 h
- Affects: Heart & nervous system
Why this verdict for dogs
Tea contains caffeine, a stimulant dogs are very sensitive to that affects the heart and nervous system.
Warning signs to watch for
- Restlessness
- Rapid heart rate
- Tremors
⚠ If your dog ate tea
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.
Tea is not a drink most people think of as dangerous, but it belongs to the same family of stimulants as coffee and chocolate. The bigger risk is often not the brewed liquid at all — it is a dog eating the used tea bags out of the bin.
How much is safe?
Caffeine toxicity in dogs starts to show around 20 mg per kg of body weight, with serious signs above roughly 40 mg/kg. A cup of black tea contains around 40 to 70 mg of caffeine, so a lapped mug is usually a minor event for a large dog and a real one for a small one. A pile of used tea bags, however, delivers a concentrated dose plus a bag that can obstruct the gut. Green tea, matcha and caffeine-heavy blends are stronger, and some herbal teas contain their own problem ingredients.
What happens if a dog eats too much?
Caffeine is a stimulant, so the picture is restlessness and hyperactivity, panting, a racing heart, vomiting, tremors and increased urination, typically within one to two hours. High doses cause dangerous heart rhythms, a rising body temperature and seizures. Cats are affected at proportionally smaller amounts.
⚠ What to do if your dog ate tea
Call a vet or poison line with your pet's weight, the type of tea and how much was consumed (ASPCA 888-426-4435 · Pet Poison Helpline 855-764-7661), and mention explicitly if tea bags were eaten rather than liquid drunk. Treatment is decontamination if it is early, then fluids and heart monitoring. A pet that is trembling or has a pounding heart needs to be seen rather than watched.
⚠️ Worried your pet got into this?
Frequently asked questions
Is decaf tea safe for dogs?
Safer, since the caffeine is largely removed, but there is no reason to offer it. Water is what dogs need, and some herbal blends contain ingredients that are toxic in their own right.
My dog ate a used tea bag — what should I watch for?
Restlessness, panting, a fast heart rate and vomiting over the next couple of hours, plus signs of obstruction over the following days. Call for advice on both fronts.
More drinks 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