Chocolate poisoning in dogs is a more frequent affection at the time of the Christmas and Easter holidays (2nd cause of poisoning in dogs after anti-coagulants). Some owners give their dog a few pieces of chocolate, thinking they’ll be happy. But it is most often accidental poisoning, a box of chocolates that remains for example on a table, or on an unclosed shelf. Chocolate is very palatable and can therefore ingest in large quantities by dogs.
Chocolate contains a substance toxic to domestic carnivores: theobromine. Depending on the dose ingested and the dog’s weight, this poisoning can be serious, even fatal.
Toxicity
The higher the cocoa content of chocolate, the more theobromine it contains. As an indication, the theobromine contents are:
- About 1600 mg in 100 grams of classic dark chocolate
- About 200 mg in 100 grams of milk chocolate
- Virtually no theobromine in white chocolate
Doses of theobromine of 100 to 250 mg per kilogram are toxic in dogs. Thus, for a 10 kg dog, an amount of 60 grams of dark chocolate can prove potentially lethal. In practice, a “small” square of chocolate weighs around 5g.
Symptoms
Theobromine is an alkaloid substance, from the methylxanthine family as is caffeine. Like the latter, it has exciting properties on the central nervous system and on the heart muscle in particular.
Symptoms are of several types, depending on the dose ingested:
- Digestive symptoms: repeated vomiting, diarrhea, excessive salivation, increased amount of water drunk, digestive spasms
- Nervous symptoms: restlessness, tremors, excitement, balance disorders, more rarely prostration, convulsions or even coma
- Cardio-respiratory symptoms: increased or decreased respiratory rate, cardiac arrhythmias
- General symptoms: hyperthermia, dehydration, increased amount of urine
Theobromine is slowly eliminated from a dog’s body. Symptoms appear a few hours after ingestion, and may persist for 24 to 48 hours, or even longer.
The first symptoms are usually digestive symptoms due to the irritant action of theobromine on the digestive tract. Then, when the molecule passes into the bloodstream, nervous and cardio-respiratory symptoms appear.
When the amount ingested is large, death can occur within 24 hours of ingestion. If the dog is still alive after 48 hours, the prognosis is rather favorable.
As theobromine is slowly eliminated from the body, symptoms of intoxication can appear in dogs consuming small amounts of chocolate every day.
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Treatment of chocolate poisoning in dogs
Either way, the sooner your dog receives care, the better the prognosis. As soon as you notice your dog has eaten chocolate, call your vet and explain what and how much he ate. He will judge the need to receive your animal in consultation. He may possibly implement a treatment to limit the absorption of theobromine, with a treatment to make him vomit or charcoal. Gastric lavage may possibly be considered during massive ingestion.
There is no specific antidote for theobromine. The veterinarian will therefore set up symptomatic treatment: treatment for the digestive system in particular (anti-diarrhea, anti-emesis), treatment for the heart (anti-arrhythmics) and neurological (anti-convulsant) if necessary. Hospitalization may be recommended to put the animal on a drip and keep it under surveillance.
Additional examinations, in particular blood tests or cardiac examinations, may be necessary for treatment and to clarify the prognosis.
Prevention
The best prevention is obviously not to give your dog chocolate. You should also store chocolate bars and boxes in a place that you are sure they cannot access. This little pleasure can indeed have serious consequences. There are plenty of other safe and effective ways to please your dog.