Chocolate Poisoning In Dogs: Symptoms, Causes, & Treatments
DR. UDAY KUMAR,PET CONSULTANT,HAZIPUR
The main ingredient of chocolate is cocoa. The cocoa bean contains two methylxanthines – naturally occurring stimulants found in foodstuffs. These two toxic drugs are theobromine and caffeine, which are especially toxic to dogs, but also for cats and other animals.Theobromine is toxic to dogs as they are unable to metabolise the drug as quickly as us humans can. It is because of this slow metabolization that theobromine builds up to a level that is toxic to their system, resulting in chocolate toxicity. Caffeine, while also toxic to dogs is present in much smaller concentrations.
Chocolate is derived from the roasted, ground seeds of the cacao tree and contains the methylxanthine theobromine – a chemical similar to caffeine. Theobromine acts as a diuretic, heart stimulant, blood vessel dilator and smooth muscle relaxant in animals and humans. Dogs metabolize theobromine very slowly, thereby enhancing the effects and toxicity to these pets. Chocolate ingestion is a common causes of canine poisoning and can lead to illness and death. Contact a veterinarian immediately if you suspect your pet has eaten chocolate. Chocolate is toxic as it contains the methylxanthine theobromine. Theobromine is similar to caffeine and is used medicinally as a diuretic, heart stimulant, blood vessel dilator, and a smooth muscle relaxant. Theobromine can be poisonous and result in severe clinical signs, especially if untreated.
Etiology
- Theobromine is a methylxanthine occurring as the major alkaloid in chocolate and cocoa powder. Chocolate is made from the fermented, dried then roasted beans of Theobroma cacao.
- Chocolate also contains a small amount of caffeine (also a methylxanthine).
- The type of chocolate is defined by the quantity (percentage) of cocoa solids the chocolate contains.
- Cocoa mulch used in gardening is also a potential source of theobromine.
- Some laxatives (usually senna-based) contain theobromine.
Pathophysiology
- Toxic effects in dogs occur at theobromine doses of 20 mg/kg, with severe signs at 40-50 mg/kg and seizures at 60 mg/kg.
- Deaths have occured after ingestion of 80-300 mg of theobromine/kg body weight.
- The amount of theobromine in products will vary due to natural differences in cocoa beans and the formulation of the products.
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- Milk chocolate contains 1.0-2.1 mg theobromine/g.
- Dark or plain chocolate contains around 0.4-8.8 mg theobromine/g.
- White chocolate and cocoa butter contain a negligible quantity of theobromine.
- Cocoa powder can contain 4.6-38 mg theobromine/g.
- Cocoa mulch can contain 10-30 mg/g.
- Rapidly absorbed from small intestine.
- Excreted in urine.
- Theobromine inhibits phosphodiesterase, thereby increasing cAMP concentrations and causing catecholamine release.
- Antagonize adenosine receptors and inhibit phosphodiesterase → stimulate myocardial and skeletal muscle contraction.
SIGNS OF CHOCOLATE TOXICITY IN DOGS
Now that you understand why chocolate is dangerous for dogs, it’s important to be able to identify when your pet may be suffering from this poisoning.
Signs of chocolate toxicity in dogs include:
Symptoms may not appear until 6-12 hours after chocolate ingestion. Symptoms that your pet may have chocolate toxicity include:
- Vomiting
- Drooling
- Diarrhea
- Extreme thirst
- Increased urination
- Hyperactivity
- Pacing
- Panting
- Muscle tremors
- Seizures
VOMITING AND DIARRHEA
These two problems are the earliest signs of chocolate toxicity in dogs. In light cases, dogs may simply vomit or have diarrhea a few times and then feel better.
However, in severe cases, these symptoms may progress further to the others on the list below.
EXCESSIVE THIRST AND URINATION
Since both theobromine and caffeine are diuretics, dogs may show both excessive thirst and urination when they have ingested too much of either of these substances.
RESTLESSNESS
Caffeine, in particular, may cause dogs to behave restlessly. Darker chocolates with higher caffeine contents may lead to this symptom even without the dog ingesting very much of it.
HIGH HEART RATE
An elevated heart rate is a dangerous symptom that could lead to cardiac arrest, especially in older dogs or those with underlying conditions. It can be difficult to monitor your pet’s heart rate at home, so it may be advised to take him to your nearest vet right away for monitoring and/or treatment.
SEIZURES
Seizures are one of the most severe symptoms of extreme chocolate toxicity in dogs. This may only occur when a dog has ingested a large quantity of chocolate, but it can sometimes mean the toxicity will become fatal without veterinary treatment.
Take your dog to the vet right away if he shows this symptom after eating chocolate.
If your dog has ingested a potentially toxic amount, they will begin to show signs and symptoms of poisoning between four to 24 hours after eating the chocolate.
Early signs are mild and include:
- Gastrointestinal upset
- Vomiting
- Diarrhoea
- Excessive urination
- Increased thirst
Signs can progress to include:
- Hyperactivity
- Increased heart rate
- Hyperthermia
- Pancreatitis
The more severe signs include:
- Depression
- Heart arrhythmias and heart failure
- Tremors
- Seizures
- Coma
What types of chocolate are toxic to dogs?
All types of chocolate are dangerous for dogs, but dark chocolate is the most toxic as it contains high amounts of theobromine. Although chocolate contains varying levels of theobromine and cocoa powder is the most harmful. Bakers chocolate, semi-sweet chocolate and unsweetened chocolate also contain high levels of theobromine. Chocolate-covered espresso beans, nuts and raisins are also dangerous for dogs. In comparison, milk chocolate contains lower levels of theobromine.
Causes of Chocolate Poisoning in Dogs
The type and amount of chocolate ingested by your pet will determine the level of severity. The more concentrated the level of theobromine in the chocolate, the more toxic the dose.
0.2 ounces of baker’s chocolate is sufficient to cause symptoms of toxicity in a 10-pound dog. 1.6 ounces of milk chocolate is sufficient to cause symptoms of toxicity in a 10-pound dog.
Concentrations of theobromine in various forms of chocolate (generalizations):
- White chocolate – 1mg/ounce
- Milk chocolate – 60mg/ounce
- Semi-sweet chocolate – 260mg/ounce
- Dark chocolate – 300mg/ounce
- Baking chocolate – 450mg/ounce
- Cocoa shell yard mulch – 300-1200mg/ounce
Though white chocolate and milk chocolate have lower levels of theobromine, the sugar and fat content can cause potentially life-threatening pancreatitis.
Theobromine levels and effect on the body:
- 20mg theobromine per kg body weight – mild gastrointestinal symptoms
- Greater than 40mg/kg – heart arrhythmias
- Greater than 60mg/kg – muscle tremors, seizures
Diagnosis of Chocolate Poisoning in Dogs
If you suspect your pet has eaten chocolate, treatment is initiated immediately without waiting for official diagnosis. Try to calculate how much the pet has eaten (how many candy bars, brownies, cake) and note the type and brand of chocolate (have the packaging available if possible). Be sure when scheduling a veterinarian appointment to tell her how much your pet weighs, describe when you think your pet ate the chocolate, how much, and of what type.
If the pet has not eaten a toxic amount of chocolate, a veterinarian may ask you to induce vomiting at home and/or carefully monitor your pet for symptoms over the next 4-6 hours.
If the pet has eaten a potentially toxic amount of chocolate in the last 1-2 hours, your vet will ask you to induce vomiting at home or bring the pet to the clinic to induce vomiting. The goal is to induce vomiting as quickly as possible. After 2 hours, the toxin has already entered the bloodstream and it may be too late for vomiting to aid in treating toxicity.
Your veterinarian will take a thorough history to determine whether your pet has gotten into trash, cocoa shell yard mulch, or other toxic substances or whether another underlying cause of symptoms is present. A complete physical exam will help in diagnosis.
Blood analysis (complete blood cell count and chemistry) and urinalysis will aid in detection of disease or organ failure. Electrocardiography (EKG) can detect heart arrhythmias and abnormalities. Radiographs may aid in ruling out other causes for symptoms.
Treatment of Chocolate Poisoning in Dogs
By the time symptoms of chocolate poisoning appear, supportive therapy is the only treatment. There is no antidote for chocolate toxicity.
Inducing vomiting
Induction of vomiting must be done within 2 hours of chocolate ingestion to be effective. If you are too far from the veterinary clinic, your vet may ask that you induce vomiting at home. Follow the instructions given by your veterinarian carefully.
If you decide to take your pet to the clinic to induce vomiting, the veterinarian will use a drug to induce vomiting right away.
Activated charcoal absorption
In cases of chocolate ingestion, the veterinarian will often give a solution of activated charcoal orally to absorb any remaining theobromine from the gastrointestinal tract.
After vomiting induction and/or charcoal treatment, your pet will need to be monitored for symptoms for 4-6 hours. If symptoms occur, supportive therapy will be required to keep your pet safe and stable until toxicity wears off. This can take up to 72 hours.
Supportive therapy
Intravenous fluid administration can help to dilute theobromine levels in the bloodstream and promote excretion. Benzodiazepines (valium) may be administered to control seizures and muscle tremors. Anti-arrhythmic medications can aid in controlling heart arrhythmias.
Recovery of Chocolate Poisoning in Dogs
A pet that has been treated for symptoms of chocolate poisoning will need to be monitored until symptoms reside. Recovery from chocolate toxicity depends on the severity and how soon treatment was administered. Recovery can be complete and prognosis good if caught and treated early (within 2 hours of ingestion).
Chocolate poisoning can be lethal at high doses. Always keep chocolate out of reach of your pet. Hiding chocolate is not sufficient since chocolate has a strong smell and a pet can find it. Keep chocolate where a pet cannot get to it (high up and in a sealed container).
REFERENCE-ON REQUEST.
https://www.pashudhanpraharee.com/common-poisoning-in-dogs/
https://vcahospitals.com/know-your-pet/chocolate-poisoning-in-dogs
