Chocolate Toxicity: 10 Facts

The ingredients that pose toxicity in chocolate are theobromine and caffeine, which are both categorized into a group of compounds called methylxanthines. 

These compounds act as stimulants that can cause tremoring, increased heart rate or arrhythmias, seizures, smooth muscle relaxants that can cause gastrointestinal upset, and diuretics that can cause urinary incontinence. 

Not all chocolates contain the same amount of theobromine and caffeine, with the largest amount being in unsweetened baking chocolate, and the least being in white chocolate. 

If chocolate ingestion is suspected, the first thing to do would be to go to the closest veterinary clinic so vomiting can be induced. This is so the ingested chocolate can be brought back up and delay any further absorption of the toxins. 

The clinician on duty will likely want to know around what time the chocolate was ingested, what type of chocolate was ingested, and approximately how much. 

If over 2 hours have passed, the pet can then be treated for the clinical signs that are present from the toxin exposure. 

Treatment for these signs could include hospitalization with fluids, heart rate monitoring, anti-seizure medications if indicated, or potential outpatient therapy. 

The clinical signs of toxin exposure often range depending on the dose of chocolate ingested. Meaning if a small dog eats a large amount of unsweetened baking chocolate (since this has the highest theobromine and caffeine content) this dog had a very high dose of chocolate ingestion. Increased heart rate, arrhythmias, and seizure-like activity occur at higher doses, while gastrointestinal upset is more likely to occur at lower doses. 

The clinical signs of chocolate ingestion can last anywhere from 12-36 hours depending on if vomiting was induced or not. 

Prognosis is generally good following chocolate toxicity. However, if the pet suffers from seizures or arrhythmias then the prognosis becomes more guarded.