You are correct with regards to Chocolate being
unsafe to consume for our companion animals. Over
consumption of chocolate can cause serious
illness and perhaps death. Chocolate contains an
ingredient called Theobromine. It is the ingredient
that can cause harm to our dogs and cats. Dogs and
cats, unlike us humans, do not possess the enzyme to
break down theobromine. Therefore, theobromine
accumulates within the body after time. Your pet may
not be ill the first time he/she consumes chocolate
but after time your pet consumes more chocolate
toxicity can occur. After saying this, Bakers Dark
Chocolate contains more theobromine than milk
chocolate. Therefore, a toxicity to chocolate can
occur more readily when consumption of Dark
Chocolate than milk chocolate. It is best if
Chocolate is not consumed at all.
If chocolate is consumed, the following toxicity
symptoms may occur: vomiting, diarrhea, diuresis
(urinary incontinence), hyperactivity, rapid
breathing/heartbeat, muscle tremors, seizures, coma.
Dangerous Quantities of Chocolate:
Amount of Dogs Weight
Amount of Milk Chocolate
Amount of Unsweetened Chocolate
Approximate mg of Theobromine
||2 1/2 oz.
||1 3/4 lbs.
||3 1/4 oz.
||2 1/2 lbs.
||4 1/2 oz.
||5 1/2 oz.
||3 3/4 lbs.
||6 3/4 oz.
||4 3/4 lbs.
||8 1/2 oz.
Here are some web sites for you to peruse:
From Tufts Newsletter:
Theobromine causes different reactions to
different dogs: dogs with health problems,
especially epilepsy, are more affected by
theobromine than healthy dogs. Theobromine can
trigger epileptic seizures in dogs prone to or at
risk of epilepsy. The size of the dog will also be a
major factor: the smaller the dog, the more affected
it is by the same amount than a larger dog.
Therefore, toxicity is described on a mg/Kg basis.
Furthermore, theobromine can cause cardiac
irregularity, especially if the dog becomes excited.
Cardiac arythmia can precipitate a myocardial
infarct which can kill the dog.
Theobromine also irritates the GI tract and in
some dogs can cause internal bleeding which in some
cases kills them a day or so later.
Chocolate - active ingredient = theobromine:
* The half life in the dog is 17.5 hours
* The Toxic dose in the dog is 100-150 mg/kg.
+ A kilogram (kg) = 2.2 lbs.
+ A milligram(mg) = 1/1000 of a gram
So for a 50 lb. dog a toxic dose would be roughly
2.2 grams (2200 mg) of pure chocolate.
However the concentration of theobromine varies
with the formulation of the chocolate so:
* Milk chocolate has 44mg/oz (154mg/100gm): toxic
dose for 50 lb dog - 50 oz of milk chocolate.
* Semisweet chocolate has 150 mg/oz
(528mg/100gm): toxic dose for 50 lb dog - 15 oz of
* Baking chocolate 390mg/oz (1365 mg/100gm):
toxic dose for 50 lb dog - 5 oz of baking chocolate
Thus a dog eating one oz of baking chocolate
would have to eat almost 3 oz of semisweet or 10 oz
of milk chocolate to get the same dose of