Is dark chocolate safe for dogs to eat?

No, dark chocolate is toxic to dogs and should never be given intentionally or left in an accessible place. Dark chocolate contains high concentrations of theobromine and caffeine - two methylxanthine compounds that dogs metabolise far more slowly than humans. While a human can safely process these compounds within a few hours, a dog's body holds onto them for 12–18 hours, allowing toxic levels to accumulate.

The danger increases with the cocoa percentage. Baker's chocolate and dark chocolate are most dangerous; milk chocolate is moderately toxic in larger quantities; white chocolate contains negligible theobromine. Even 20g of dark chocolate per kilogram of body weight can be fatal.

Symptoms typically appear within 6–12 hours and include: vomiting, diarrhoea, excessive thirst and urination, restlessness, rapid heart rate, muscle tremors, and seizures. In severe cases, cardiac arrhythmias and death can occur.

If your dog has eaten chocolate, call your vet or the ASPCA Animal Poison Control Center (888-426-4435) immediately. Do not wait for symptoms to appear - early intervention (inducing vomiting within 2 hours) is far more effective.