Can dogs eat chocolate?
Toxic. No. Chocolate contains theobromine and caffeine, which dogs clear far more slowly than people do.
How much is dangerous?
Merck reports mild signs from about 20 mg/kg of methylxanthines, cardiac signs from about 40 to 50 mg/kg, and seizures from about 60 mg/kg. Darker chocolate carries far more theobromine per gram than milk chocolate.
Why it does harm
Theobromine and caffeine are methylxanthines. They block adenosine receptors and raise intracellular calcium, which overstimulates the heart and central nervous system. Dogs metabolize theobromine much more slowly than humans, so it accumulates.
What to look for
- Vomiting and diarrhea
- Restlessness, hyperactivity and panting
- Increased thirst and urination
- Racing or irregular heartbeat
- Tremors and, at high doses, seizures
Timing. Usually within 6 to 12 hours, sometimes sooner.
What to do
- Work out the dose with the chocolate toxicity calculator — the type of chocolate matters more than the amount.
- Call your vet or a pet poison control line with the weight of your dog, the type of chocolate and the amount.
- Do not wait for symptoms. Decontamination works best early.