As with all harmful substances, the effect depends on the dose. Therefore, white chocolate will hardly give any problems, as it barely contains any cocoa. Milk chocolate can cause signs of poisoning in cats or dogs when more than 30 grams per kilograms of bodyweight is consumed. For dark chocolate this is 15 grams per kilograms of bodyweight.
The signs of chocolate poisoning are: Restlessness, nervousness, nausea, shaking, trembling, vomiting and diarrhoea. This can worsen to hyperactivity, an increase in heart rate, fever and muscle twitching. It can even lead to coma and death. Due to the high amount of fat, the pancreas may become infected two or three days after the chocolate is consumed. Damaging of the heart muscle can also still occur several days later and may lead to death.
When an animal has eaten chocolate, it should vomit as soon as possible. Put a spoonful of salt in the mouth and let the animal swallow it. Vomiting should occur within 5 minutes. If not, alarm your vet. The websites of vets often give useful information on how to deal with chocolate poisoning.