How dangerous can Chocolate be to your Pet?
this article was published in PVMA NEWS  February edition and submitted by Heidi Houchen, DVM and they have allowed us to
 reprint this article on our web page.  We thank them and hope you find this information helpfull.

                                                            For The Love of Chocolate
                                                  Submitted by Neidi Houchen D.V.M.

At Dove Lewis, the incidence of chocolate toxicity seems to peak between the months of November and 
February.  This may reflect increased chocolate availability during the holidays -- or increased chocolate 
consumption during the Northwest's rainy season-you be the judge! Regardless of the reason, chocolate 
is a favorite food of dogs as well as humans and its presence can tempt even the most discriminating of 
canine palates to indulge.

The most toxic component of chocolate is the methylxanthine, theobromine, a relative of caffeine and 
theophylline. Theo-bromine can exert a wide range of pharmocologic effects, most notably stimulation of the 
cardiac muscle and central nervous system. The acute lethal oral dosage of theobromine in dogs is 100 - 200 
mg/kg and 80 - 150 mg/kg in cats. However, there is wide variation in individual sensitivity to 
methylxanthines.  Toxic effects of theobromine can be seen as low as 20 mg/kg.  In dogs, theobromine is 
readily absorbed from the gut and has a very long half-life (17.5 hours) in comparison with other species. 
Because of the rate of absorption exceeds the rate of elimination, the long half-life may be responsible for the
 chronic chocolate poisoning seen in the dog.

Clinical signs of chocolate toxicity can vary from mild to se-vere. Brain stimulation by theobromine can result 
in tachypnea, vomiting, restlessness, tremors and even seizures It also stimulates cardiac muscle which can
 result in tachycardia and arrhythmias. Like caffeine, theobromine can induce diuresis and excessive urine
 production is often seen with chocolate toxicosis. Death can occur from cardiac arrhythmias or respiratory 
failure. Because there is no specific antidote for chocolate toxicosis, treatment is symptomatic. It is important 
to pre-vent further absorption, hasten elimination and maintain basic life support. If the patient is comatose 
or convulsing, gastric lavage should be performed-otherwise vomiting should be induced as soon as possible.
 Because the half-life of theobromine is long and because chocolate tends to stay in a solid or semiplastic state 
in the stomach, repeated doses of activated charcoal should be administered every 4 hours for up to 72 hours 
after ingestion. The EKG should be closely monitored and if indicated, VPC's and tachycardia can be controlled 
with lidocaine, propranolol, or metoprolol. If the patient is seizuring, diazepam is the initial drug of choice 
followed by barbiturate therapy. Fluid therapy, close continuous monitoring of cardiac and neurologic status 
and supportive care are essential to a successful outcome.

This time of year at Dove Lewis we receive a large number of calls by pet owners whose dogs have ingested 
chocolate. The most frequently asked questions are "How much is too muchchocolate?" and "Should we vomit
 our pet or bring it in to be seen?". These are questions that are not quickly or easily answered for a variety of 
reasons. Most importantly, animals vary widely in their sensitivity to chocolate - i.e., schnauzers are more 
susceptible than labs (a.k.a. "the garbage guts"). Also, the amount of theobromine ingested varies depending 
on the type of chocolate consumed.  Unsweetened baking chocolate and cocoa powder contain 392 mg/ounce
 whereas milk chocolate contains 44 mg/ ounce. As a general rule, the toxic level of theobromine is considered
 to be 50 mg/lb. In addition to theobromine, chocolate often contains fat and sugar in varying amounts and 
this makes diabetic animals and animals with predisposition towards (or a history of) pancreatitis at greater
 risk for developing more severe problems from chocolate ingestion. Finally, it is important to consider the 
paper and/or foil component of individually wrapped chocolates as this may put an animal at risk for 
developing a foreign body.

In general, when dealing with an animal that has eaten chocolate, try to determine the amount and type of
 chocolate ingested. Then determine the potential toxic dose of chocolate using toxic levels of theobromine 
@ 50 mg/ pound and that one ounce of chocolate is equivalent to 30 mg. For example, only 2 ounces of
 baking chocolate as compared with 17 ounces of milk chocolate are toxic to a 15 pound dog. However, if 
the milk chocolate was contained in truffles and the animal ingesting it was an elderly schnauzer, the 
theobromine may be the last of your worries! Most importantly-"If in doubt, vomit it out".