Chocolate toxicity is one of the most common poisonings in dogs and is more common at holiday times. The compound responsible for toxicity is methylxanthine, found in chocolate, coffee, tea, and caffeinated sodas. Both theobromine (found in chocolate) and caffeine (found in both drinks and chocolate) are methylxanthines.
Poisoning is common in dogs because of their habit of rapid consumption. Although dogs are the most susceptible, the toxin has been known to affect or kill cats, birds, rodents and reptiles as well.
Clinical Signs
Clinical signs include vomiting, diarrhea, hyperactivity, restlessness, excessive urination, muscle tremors, tachycardia (elevated heart rate), bradycardia (slow heart rate), arrhythmias, hyperthermia (high temperature), seizures, coma and death. Vomiting and diarrhea can occur 2 to 4 hours after intake.
The following is a list of dangerous doses of chocolate, and are approximate amounts only. Please consult with your veterinarian if your pet has eaten any amount of chocolate. Every animal has differing levels of sensitivity to theobromine. Caffeine will enhance the toxicity of theobromine. Some brands of chocolate have more caffeine than others.
Treatment
If your pet has just eaten chocolate, consult with a veterinarian. Induction of vomiting may be recommended, however we never want to induce vomiting in an animal who is twitchy, or unaware of his/her surroundings or seizing.
Seeking immediate veterinary care allows for supportive treatment where measures may be used, such as intravenous fluids, oxygen therapy, sedation, and cardiovascular stabilizing. There is no antidote for chocolate poisoning, and a patient will be decontaminated by inducing vomiting (if safe, an ingestion has occurred in the last few hours) and administration of activated charcoal.