People commonly eat chocolate to console broken hearts or calm nervous emotions. With dogs and cats, this sweet treat also targets their heart and nervous system—but with toxic results.   

Chocolate is hazardous for pets, and although rarely fatal, can cause serious illness requiring hospitalization. Protect your pet from chocolate toxicity by learning its effect on them, its treatment, and prevention. 

A sweet stimulus—why chocolate is toxic for pets

Pets are sensitive to two stimulant chemicals in chocolate, theobromine and caffeine—the most dangerous being theobromine. While these ingredients give humans a pleasant buzz, they are poorly metabolized by pets. After chocolate is absorbed in your pet’s small intestine, theobromine and caffeine enter the bloodstream, stimulating the heart and central nervous system (i.e., nerves, spinal cord, brain), and disrupting normal function. Without treatment, chocolate’s toxic components recirculate through the liver, and are reabsorbed through the bladder, prolonging your pet’s signs and suffering for up to 72 hours. 

Pets who do not experience toxicity can still be sickened by eating chocolate. The high fat and sugar content in chocolate frequently leads to vomiting, diarrhea, and pancreatitis

Pick your poison—the worst chocolates for pets

Chocolate’s toxicity is dose-dependent and varies by type, volume consumed, and your pet’s body weight. In general, the darker or more bitter the chocolate, the higher the theobromine concentration, and the smaller the amount that will make your pet sick. From most to least toxic, common chocolates ingested by pets include:

  • Cocoa powder
  • Unsweetened or baking chocolate
  • Semi-sweet chocolate
  • Sweet dark chocolate
  • Milk chocolate
  • White chocolate

For comparison, cocoa powder contains a whopping 800 milligrams per ounce, unsweetened chocolate clocks in at 450 ms per ounce, and milk chocolate contains only 45 ms per ounce. Practically speaking, a 50-pound dog can experience toxic effects from only one ounce of baker’s chocolate, but nine ounces of milk chocolate. 

Chocolate-coated warnings—toxicity signs in pets

Pets may not show illness signs right away, as the chocolate must be digested and absorbed to reach the heart and nervous system. However, if you know your pet has consumed chocolate, do not wait until visible signs appear—call Animal Internal Medicine and Specialty Services or the ASPCA Animal Poison Control Center for assistance immediately. Appreciable signs usually occur 6 to 12 hours after ingestion, and commonly include:

  • Vomiting
  • Diarrhea
  • Increased thirst and urination
  • Restlessness and panting
  • Rapid heart rate

Cardiotoxic and neurotoxic signs can occur in severely affected pets. These signs, which are impossible to ignore, may include muscle tremors, collapse, seizures, abnormal heart rhythms, and potentially death.

Taking candy from a pet—treating chocolate toxicity

If we advise you to bring your pet to our hospital for treatment, we will start by managing any potentially unstable clinical signs, such as active or recent seizures, respiratory distress, or arrythmias. Following stabilization, we will administer activated charcoal, to soak up any remaining chocolate in your pet’s system. Close monitoring, supportive medications, and hospitalization are necessary for severely affected pets, to ensure the chocolate is cleared from their system, and that they do not relapse into arrhythmias, seizing, or complications, such as aspiration pneumonia. Clinical signs may last up to 72 hours.

Sweet outcomes—pet prognosis

When you call us, our veterinarians will triage your pet based on the chocolate type and amount consumed, and their body weight. If your pet has not ingested a toxic dose, and is not showing any illness signs, you may be told to monitor them at home, but we will ask you to bring your pet in immediately if we are concerned about their situation.

Rapid treatment can help clear chocolate from your pet’s system, and prevent their heart and central nervous system from being affected. Pets who are treated quickly have an improved prognosis, and require a shorter hospital stay. Severely affected pets may experience permanent heart or brain damage from prolonged arrhythmias and seizures.

Leave it—preventing chocolate toxicosis in pets

Resisting chocolate’s sweet seduction is as difficult for pets as for humans. However, an understanding of how and when pets are commonly exposed can help you limit their opportunities for trouble. Prevent chocolate-covered catastrophes by taking the following steps:

  • Store all chocolate candy in a closed container inside a high cabinet
  • Avoid using chocolate for decoration
  • Put away baking supplies when not in use
  • Wrap and store baked goods out of reach
  • Keep lunch boxes, bags, and purses off the floor
  • Confine your pet to a crate during parties or gatherings
  • Teach your dog to “leave it,” rather than diving for a dropped food item

Chocolate is a popular comfort food, and a staple in many homes, which explains why chocolate toxicity is consistently one of the top five poisonings reported to the ASPCA Pet Poison Control. Don’t let your pet experience too much of a good thing by preventing their access to any potential hazards. Always immediately call  Animal Internal Medicine and Specialty Services or the ASPCA Pet Poison Control Center, if your pet ingests any kind of chocolate.