Chocolate is Toxic to Dogs | Signs and First Aid

How chocolate affects dogs

Chocolate contains a group of substances known as methylxanthines and this group includes several active substances, among which, the most important are caffeine and Theobromine. Theobromine and Caffeine are similar in both structure and effects. Although, chocolate contains 3 to 10 times more theobromine than caffeine, both substances contribute to the clinical picture.

Once introduced in the organism, the theobromine and caffeine act like potent:

  • Diuretics (promote elimination of fluids from the anatomy)
  • Heart stimulants (stimulate stronger and faster contractions)
  • Blood vessel dilators (enlarge the blood vessels’ diameter, thus decreasing the overall blood pressure)
  • Smooth muscle relaxants.
Cartoon of a happy dog

Can dogs eat chocolate – Why is chocolate toxic to pets

The theobromine’s effects are same for both humans and dogs. However, humans are capable of breaking down them quickly. On the flip side, dogs tend to metabolize the theobromine slowly, thus accenting its potentially toxicity effects.

It should be noted, that theobromine poisoning causes severe clinical signs and if left untreated it can lead to various medical complications that more often than not, end fatally.

My Dog ate Choclate – How much chocolate can a dog eat

Different types of chocolate contain different amounts of methylxanthines. Therefore, not all types of chocolate are equally toxic to dogs. For example:

  • Milk chocolate – is toxic if ingested in amounts of 40 grams per kilogram of dog’s weight.
  • Semi-sweet chocolate – is toxic if ingested in amounts of 17.0 grams per kilogram of dog’s weight.
  • Dark chocolate – is toxic if ingested in amounts of 15.0 grams per kilogram of dog’s weight.

In a nutshell, the darker and more bitter, the greater toxicity it holds for dogs. This is due to the fact that unsweetened dark chocolate contain more theobromine. You can use this chocolate toxicity calculator to find out the toxic level, and watch out for symptoms to come.

The toxic dose of theobromine is as low as 20 mg/kg. At this point affected animals show agitation, hyperactivity and digestive disturbances (drooling, vomiting and diarrhoea). The cardiac signs (racing heart rate, arrhythmia, high blood pressure) begin to manifest when the ingested dose of theobromine is larger than 40 mg/kg. At doses higher than 60 mg/kg neurologic signs (twitching, seizures) develop. Doses around 200mg/kg are fatal.

It should be noted that if ingested in the right amount, any chocolate can be toxic for any dog, regardless of its body weight.

Can Dogs Eat White Chocolate

Compared to Milk chocolate or Dark chocolate, white chocolate is not that toxic, because amount of Theobromine  (component – that is toxic to dogs and other pets) is low in white chocolate. Therefore you might not see any symptoms in your dog after eating white chocolate.  We DO NOT RECOMMEND sharing any sweet with your dog, as they are high in fat. Simply there shouldn’t be any dog chocolates as they may be lethal.

What are the clinical signs of chocolate poisoning?

The symptoms of chocolate poisoning depend on several factors such as:

  • Amount of ingested chocolate
  • Type of ingested chocolate
  • Dog’s weight
  • Dog’s overall health status.
  • Empty stomach or full.

The most common symptoms of a dog suffering from chocolate poisoning are:

  • Vomiting
  • Excessive drooling
  • Diarrhoea (with chocolate-like smell)
  • Hyperthermia (increased body temperature)
  • Increased thirst
  • Pollakiuria (frequent urination)
  • Tachypnea (rapid breathing)
  • Tachycardia (increased heart rate)
  • Hypotension (low blood pressure)
  • Increased reflex responses
  • Muscle rigidity
  • Pacing
  • Hyperactivity
  • Neurological signs – twitches, tremors or seizures.

In cases of advanced intoxication, the dog may show signs like:

  • Cardiac failure
  • Weakness

How long does it take for Chocolate to Affect a Dog

Most likely you will see signs within 30 minutes, this would depend on how much chocolate your dog ate and what type of chocolate. However, because of the Theobromine’s long half-life, the clinical signs of chocolate poisoning may not become apparent immediately after the ingestion. In some cases, it may take up to 6 hours for the clinical picture to develop. What is more, due to the long half-life, once the clinical signs become apparent they can last for several days. In severe cases, they may persist for up to 72 hours. We have mentioned some symptoms you should look out for in our calculator above. The fact that the Theobromine may be re-absorbed from the bladder makes the clinical picture even more prolonged and the prognosis even more complicated.

First aid for chocolate poisoning in dogs

The first thing you need to do is determine what type of chocolate (White or Dark chocolate or Baking chocolate) and the amount. Call your vet ASAP to get his advice – You may use our this calculator as a guide. Depending on the type and amount of ingested chocolate, the veterinary surgeon will either recommend you to monitor the dog or to induce vomiting and rush to emergency vet centre. Bring your Pet insurance policy number as most of vet clinics would process claims behalf of you.

If you need to induce vomiting you can either use washing soda crystals or 3% hydrogen peroxide. Amount of hydrogen peroxide you need is depends on the weight of your dog.

When inducing vomiting you need to be extra careful.

  • Only try to induce vomiting if the dog is alert.
  • Do not induce vomiting if the dog shows signs of neurological problems, such as seizures. If a dog in this condition vomits, some of the vomit may enter its windpipe, causing aspiration pneumonia.
  • Salt poisoning may occur if you use salt for vomit induction. Therefore, in spite of certain recommendations, salt should be avoided for such purposes.

At the vet’s office

Diagnosis

The diagnosis should be based on either the history of exposure retrieved by talking with the owner and presenting clinical signs or if the owner is not aware of what happened, than on the results retrieved by examining the dog, as well as the presenting clinical signs.

The physical examination includes some additional tests like blood analysis (full blood cell count and blood biochemistry profile) and a urinalysis. To detect heart abnormalities and arrhythmias the veterinarian is likely to perform an ECG.

Treatment

Sadly, when it comes to chocolate poisoning there is no specific antidote. The treatment’s main goal is to stabilize the patient by neutralising the symptoms and eliminating the primary toxin (theobromine).

The treatment includes:

  • Decontamination through:
    • vomiting induction – this is useful only within 1 hour of the chocolate ingestion and before any clinical signs have developed. Several agents can be used to induce vomiting – apomrphine and xylazine (at the vet’s office) and washing soda crystals and 3% hydrogen peroxide (at home).
    • Gastric lavage – suitable for already sedated patients (usually due to extreme seizing)
    • Toxin absorption by using activated charcoal (1-4g/kg, PO) – in already symptomatic dogs, the activate charcoal can be used every 8 hours.
  • Symptomatic therapy – depends on present signs and may include medications that:
    • control the heart rate
      • atropine (0.01-0.02 mg/kg) for bradyarrhythmias (decreased heart rate)
      • metoprolol (0.2-0.4 mg/kg, slow IV) or propranolol (0.02-0.06 mg/kg, slow IV) for tachyarrhythmias.
    • control potential tremors and seizures
      • methocarbamol (50-220 mg/kg, slow IV) and diazepam (0.5-2 mg/kg, slow IV) for mild seizures
      • barbiturates for severe seizures.
    • Supportive therapy – Regardless of the presenting signs, the supportive therapy should include:
      • Administration of intravenous fluids – the goal is to dilute the theobromine’s levels in the bloodstream and promote its excretion
      • Placement of a urinary catheter – to prevent theobromine re-absorption through the bladder wall
      • Correction of the acid-base and electrolyte abnormalities
      • Thermoregulation maintenance.

Hospitalisation

Dogs that show severe signs of chocolate poisoning need to be hospitalised for few days or at least until stabilised.

On the bright side, in recovered dogs, there are no long-term ill effects from chocolate poisoning.

Prevention

When it comes to protecting our beloved canine babies, it is better to be safe than sorry. Dogs and chocolate does not go together. All choc products should be kept out of your dog’s reach. Since dogs are naturally curious and have a powerful sense of smell, hiding the chocolate products is simply not enough.

If your dog loves how cocoa tastes, you can indulge it by using dog treats that contain the chocolate substitute – Carob. Carob looks and tastes like chocolate.