Chocolate Toxicity in Dogs

Dog wants cookies

 Retales Botijero/Getty Images

Chocolate is a popular food item found in many households, especially around certain holidays like Valentine's Day, Halloween, and Christmas. You and your dog may love chocolate. But, eating it can be harmful and potentially fatal for them. Chocolate is one of the top 10 toxins being reported to the ASPCA. So, if you have it in your home, make sure to keep it out of your dog's reach.

Warning

If you suspect your dog has eaten chocolate, even a small amount, seek veterinary attention immediately!

Why is Chocolate Toxic to Dogs?

Theobromine is the active ingredient in chocolate that can pose a problem for dogs. Caffeine can also be found in chocolate, however, it is not as potent as theobromine. These compounds are known as methylxanthines. Although the concentration of theobromine in chocolate is three to ten times that of caffeine, both contribute to the clinical signs seen in chocolate toxicosis. The exact amount of methylxanthines in chocolate differs because of the natural variation of cocoa beans and brands of chocolate products. This article will focus mainly on the effects of theobromine.

The more chocolate liquor there is in a product, the more theobromine there is. Chocolate liquor is the liquid that results from grinding hulled cacao beans. Baking chocolate has the highest amount of chocolate liquor and is, therefore, the worst for dogs. This is followed by semisweet and dark chocolate, milk chocolate, chocolate flavored cakes or cookies. White chocolate has an insignificant amount of theobromine, but ingestion can still cause issues like pancreatitis.

Toxic doses of theobromine begin at nine milligrams (mg) per pound of the dog’s weight for mild signs. For severe signs it can soar to 18 mg per pound. Milk chocolate contains 44 mg per ounce of theobromine. Semisweet chocolate contains 150 mg per ounce. Baking chocolate contains 390 mg per ounce. So for example, if a dog weighing five pounds, consumes one ounce of milk chocolate, an owner may see mild signs. But, an ounce of baking chocolate causes more severe signs and is potentially life-threatening, if not addressed immediately.

Symptoms of Chocolate Toxicity

  • Vomiting
  • Diarrhea
  • Restlessness
  • Abdominal distention
  • Increased water intake
  • Hyperactivity
  • Increased urinary output
  • Tremors
  • Stiffness
  • Seizures
  • Death in severe cases

Clinical signs of chocolate toxicity usually occur within six to twelve hours of ingestion. Initially, owners may notice vomiting, diarrhea, abdominal distention, increased water intake, and restlessness. Signs may progress to hyperactivity, polyuria, ataxia, stiffness, tremors, and seizures. Coma may also occur, and in severe cases, death.

On physical examination, increased heart rate, increased respiratory rate, blue gums (cyanosis), hypertension, hyperthermia (temperature increase), decreased heart rate, and hypotension may be noted. Electrolyte disturbances late in the course of the toxicosis contribute to cardiac dysfunction. Death is generally due to heart arrhythmias, hyperthermia, or respiratory failure. The high-fat content of chocolate products may trigger pancreatitis in some dogs.

Treatment for Chocolate Toxicity

If you suspect your dog has eaten any type of chocolate, it is recommended that they go to their veterinarian, or the nearest emergency hospital. A dog presenting before clinical signs have developed (usually within one hour of ingestion), should have gastric decontamination performed. Inducing vomiting is appropriate for dogs that are not experiencing seizure activity.

If they are having seizures, the dog must first be sedated with medication to control the seizures before decontamination can occur. Gastric lavage is the best option in this case. Activated charcoal will also be given to prevent the recirculation of methylxanthines, which can prolong clinical signs. Repeated doses of charcoal should be administered every 12 hours in symptomatic animals for as long as signs are present.

Other treatments for symptomatic animals include fluid therapy, medications to control vomiting and heart arrhythmias, maintaining body temperature, correcting acid-base and electrolyte abnormalities, and monitoring cardiac status through electrocardiography (ECG). Sometimes a urinary catheter must be placed, because methylxanthines and their metabolites can be reabsorbed across the bladder wall. Clinical signs may persist up to 72 hours in severe cases.

How to Prevent Chocolate Toxicity

The best way to prevent this potentially fatal condition is to keep your dog away from chocolate. Keep it out of your dog's reach. Make sure that everyone in the household, especially children, understand how dangerous it can be for their dog to get chocolate in any form. If there is exposure, even in small amounts, seek veterinary attention immediately. Early intervention is the key to a favorable prognosis.

References