Why chocolate is toxic to dogs
Chocolate contains theobromine and caffeine — stimulants that dogs break down far more slowly than people. The darker and more bitter the chocolate, the more theobromine, and the more dangerous it is. Baking chocolate and cocoa powder are the worst, followed by dark, then milk; white chocolate has almost none but is still fatty and sugary.
What to do if your dog ate chocolate
Act fast — don't wait for symptoms. Note your dog's weight, the type of chocolate, and roughly how much, then call your vet or poison control: ASPCA (888) 426-4435 / Pet Poison Helpline (855) 764-7661 (US). Our chocolate toxicity calculator estimates the risk by weight, type, and amount while you call.
Symptoms of chocolate poisoning
Signs usually appear within 6–12 hours and can last up to 72 hours: vomiting, diarrhea, restlessness, excessive thirst and urination, a racing or irregular heartbeat, muscle tremors, and in severe cases seizures. Puppies, seniors, and dogs with heart conditions are at higher risk.
Frequently asked questions
My dog ate a little milk chocolate and seems fine — is that okay?
Maybe, but symptoms can take hours to appear. Use the calculator and call your vet if it shows anything above low risk, especially for a small dog.
Is white chocolate safe?
It has almost no theobromine, so poisoning is unlikely, but the high fat and sugar can still cause stomach upset or pancreatitis.
How long does chocolate stay in a dog's system?
Theobromine has a long half-life in dogs (around 17–18 hours), so effects can persist for up to 72 hours.
Related: chocolate toxicity calculator · full food checker · peanut butter.