Q: My dog recently swallowed a small amount of chocolate (about the size of a 50 cent coin) and subsequently vomited. He’s been eating and drinking normally and hasn’t showed any discomfort since, but I’m afraid that even if he is in pain, he may not show it. What should I look out for?
A: Thankfully, your dog only swallowed a small piece of chocolate and he managed to vomit after. Chocolates are known to be toxic in dogs, and more so in cats; so it’s very important that you keep it well out of reach of your pets!
Chocolate is made by roasting the seed of the Theobroma cacao, which contains both caffeine and theobromine. The amount of theobromine present is approximately three times more than caffeine and both contribute to the signs of chocolate toxicity. The reason dogs cannot consume chocolate is that they do not break down theobromine well in their system, resulting in toxicity.
In mild chocolate poisoning, the clinical signs are vomiting, diarrhea, panting, high body temperature and fast heartbeat. In severe cases, the dog can have seizures, inability to walk, heartbeat irregularities, heart attacks, coma and even death.
Not all chocolates contain the same amount of theobromine. Refer to this as a guide:
None to very low amounts of theobromine
2.5mg of theobromine
Semisweet / Dark Chocolate
5.5mg of theobromine
16mg of theobromine
28mg of theobromine
Theobromine ingestion will manifest itself in different forms depending on the amount ingested and metabolised. If your dog swallows 20mg/kg bodyweight, then he may show signs of vomiting, diarrhoea and increased thirst. For a 5kg canine, it will take about 40g of milk chocolate or 20g of dark chocolate to cause such problems.
If you discover that your pet has eaten chocolate, quickly offer it plenty of water to drink. Try to determine the amount of chocolate it might have eaten (eg. in grams). Be sure that you have an accurate weight of your dog too.
In severe poisoning, your pet will need blood tests to check its kidney and liver functions, and hospitalisation and fluids therapy. In your case, it is good that your dog has vomited after the chocolate ingestion, which means that it is unlikely that the chocolate has been absorbed. However, theobromine can stay in the body for as long as 18 to 72 hours. So do schedule an appointment with your vet for a thorough physical examination.
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