While an occasional chocolate chip probably won't cause much more than an upset tummy for Fido, it won't help provide him with any immunity against chocolate poisoning. Eating small amounts of chocolate or foods containing chocolate over any period of time won't do anything other than make your pup sick and doesn't help to make the toxins in chocolate less harmful for him.
Chocolate: Tasty but Toxic to Canines
Chocolate contains alkaloids that are harmful to dogs called methylxanthines, which include theobromine and caffeine, along with a high amount of fat. The most dangerous kinds are bitter dark chocolates including baker's chocolate, because contains the highest concentration of methylxanthines. Milk and white chocolates contain the lowest amounts of these toxins and it will take larger amounts of them to poison your dog. For example, baker's chocolate is eight times more toxic to your pooch than milk chocolate, warns the American Society for the Prevention of Cruelty to Animals. Only 1/2 ounce of baker's chocolate can be very toxic to a small, 10-pound dog.
The More Chocolate Fido Eats, the Worse He Feels
A dose of theobromine, the main toxin in chocolate, large enough to cause minor poisoning symptoms is around 9 mg per pound of weight, according to the VCA Animal Hospitals website. Considering that an ounce of milk chocolate contains between 44 and 58 mg of theobromine per ounce, this means that a 10-pound dog will exhibit poisoning symptoms when he eats around two to three ounces of milk chocolate. The Fairhaven Veterinary Hospital warns that this is typically the equivalent found in one chocolate bar. Larger doses of theobromine, around 100 mg per pound of weight, can be fatal if ingested by your dog, around 10 chocolate bars' worth for a 10-pound dog.
What Happens When Fido Indulges in Chocolate Snacks
Dogs process theobromine differently than humans, which is why it's so dangerous for them. Symptoms including vomiting, diarrhea, hyperactivity, drooling, frequent urination, elevated heartbeat, tremors, seizures and even cardiac arrest can occur after your pup eats chocolate in toxic doses. Theobromine also has a very long half-life in the body and can be reabsorbed from the urine that builds up in your pooch's bladder. Symptoms can continue for several days as your pup works to excrete the toxins contained in chocolate. For this reason, giving your pup small amounts of chocolate over a period of days can actually lead to a toxic dose due to the remaining theobromine in the body.
Sorry, No Immunity
Chocolate and other cocoa-containing products don't become less harmful to your pup over time and he can overdose on them if he eats small amounts of them daily. Even white chocolate, which is low in theobromine, contains high amounts of fat that can result in canine pancreatitis, warns the ASPCA. Although your pup may not get sick if given very small amounts of chocolate occasionally, this doesn't mean that it is no longer toxic for him. Avoid giving any chocolate to your pooch and visit the vet if he has gotten his paws on some. Depending on his symptoms and the amount of chocolate he ate, your vet may recommend hospitalization until he's symptom-free.