Chocolate is toxic to dogs and can cause significant illness, depending on the type and amount of chocolate consumed and the weight of the dog. Theobromine and caffeine are two chemicals found in chocolate that are poisonous to dogs. Dogs cannot metabolize these chemicals as well as humans can, and the darker and more bitter the chocolate, the greater the danger. The symptoms of chocolate poisoning usually appear within six to 12 hours after ingestion and may last up to 72 hours. The symptoms include:

• Vomiting
• Diarrhea
• Restlessness
• Increased thirst
• Panting
• Tremors
• Elevated or abnormal heart rate
• Seizures
• Collapse

If you suspect that your dog has eaten chocolate, it is important to seek medical attention by calling your veterinarian or Pet Poison Helpline as soon as possible. Even if the amount ingested is not a toxicity concern, dogs can still become ill from the fat and sugar in chocolate, which can cause pancreatitis in severe cases or in dogs that have more sensitive stomachs. The prognosis for chocolate poisoning can be worse if complications such as developing aspiration pneumonia from vomiting occur.