Chocolate Poisoning In Dogs
Chocolate is a beloved treat for many humans, but it's a different story when it comes to dogs. Chocolate poisoning in dogs is a serious and potentially life-threatening condition that every pet owner should be aware of.
Why is Chocolate Toxic to Dogs?
The culprit behind chocolate’s toxicity in dogs is a compound called theobromine, which is similar to caffeine. While humans can easily metabolize theobromine, dogs process it much more slowly, allowing toxic levels to build up in their system. The amount of theobromine varies depending on the type of chocolate:
White Chocolate: Contains the least amount of theobromine but can still cause issues if consumed in large quantities.
Milk Chocolate: Contains a moderate amount of theobromine.
Dark Chocolate and Baking Chocolate: Contains the highest levels of theobromine and are the most dangerous
OVERVIEW
Sudden (acute) gastrointestinal, nervous system, and heart problems are caused by excessive intake of chemicals (known as methylxanthine alkaloids, such as theobromine and caffeine) present in chocolate
These are also found in diet pills, some herbals, and cocoa bean hulls (the latter is used for garden mulch)
Dogs are poisoned most frequently based on their non-selective appetite, their access to chocolate or methylxanthine-containing products, and their ability to consume large amounts of chocolate or other items containing the toxins
Other species may be affected, but they have a more limited access to chocolate and cocoa bean hull mulch than dogs; cocoa bean hulls may be a source of poisoning in horses and poultry
Theobromine is the chemical that is at the highest concentration in chocolate products and in cocoa bean hull mulch; caffeine is in a much lower concentration in these products
Theobromine has a longer half-life in dogs than in people, meaning that it stays in the dog's body for a longer time period than it does in people
Cocoa bean hull mulch is an increasingly popular product for using around gardens; it is composed of the shells (or hulls) of the cocoa bean and is produced during processing of the bean for chocolate
Signalment/Description of Pet
Dogs and rarely cats
Small dogs—may be more at risk (amount of chocolate available compared to dog's body weight)
Puppies and young dogs—may be more likely to ingest large amounts of unusual foods, such as chocolate or chocolate-containing foods, or cocoa bean hull mulch and less able to process the active chemicals due to immaturity of the body systems
Signs/Observed Changes in the Pet
Signs are seen after recent chocolate or cocoa bean hull ingestion (family may find evidence of chewed containers or remnants of packaging from chocolate or chocolate-containing products
Vomiting and diarrhea—often the first reported signs; occur 2–4 hours after ingestion
Early restlessness and increased activity or nervousness
Frequent urination (known as “polyuria”)—may result from diuretic action of chemicals in chocolate
Blood in the urine (known as “hematuria”)—occasional sign
Advanced signs—stiffness; excitement; seizures
Increased body temperature (known as “hyperthermia”)
Exaggerated reflexes (known as “hyperreflexia”)
Muscle rigidity
Dilated pupils (known as “mydriasis”)
Rapid breathing (known as “tachypnea”) and poor oxygenation
Rapid heart rate (known as “tachycardia”)—heart rate may reach 200 beats per minute or more
Irregular heartbeats (known as “arrhythmias”)
High blood pressure (known as “hypertension”)
Increased thirst (known as “polydipsia”)
Coma, and sometimes death—12–48 hours after ingestion
Causes
Usually some form of processed chocolate (used for baking and candies, less in milk chocolate)—baker’s chocolate contains especially high concentrations of theobromine and caffeine
Caffeine stimulant pills
Dogs—eating cocoa bean hulls used as garden mulch
Risk Factors
Dogs—most commonly affected because they consume large amounts of many foods quickly
Chocolate—highly palatable or tasty and attractive; often readily available and unprotected in homes and kitchens, especially around the holidays when chocolate products and candies are common
Use of cocoa bean hull mulch in the garden
TREATMENT
Health Care
Describe the type of chocolate and amount of exposure to your veterinarian; take your pet to a veterinary hospital as a potential poisoning emergency
Fluid therapy—prevent dehydration and promote production of urine; correct electrolyte disturbances caused by vomiting, as necessary
Control seizures
Detoxification (if not having seizures or seizures are controlled)—your veterinarian may induce vomiting (known as “emesis”), flush the stomach with fluids (known as “gastric lavage”), and administer activated charcoal
Control overheating (hyperthermia)
Treat rapid heart rate (tachycardia)
Allow pet to urinate frequently or catheterize the bladder to remove urine to reduce the possibility of the methylxanthines being reabsorbed into the body from the urine
Activity
Avoid stress and excitement as these could make nervous system signs (such as hyperreflexia or seizures) worse
Diet
Suddenly (acutely) affected pet—do not feed
Recovering or convalescent pet—bland diet for several days to allow recovery from gastrointestinal problems
Surgery
Rarely, a solid mass or hard lump of chocolate could form, which must be removed surgically
Medications
Medications presented in this section are intended to provide general information about possible treatment. The treatment for a particular condition may evolve as medical advances are made; therefore, the medications should not be considered as all inclusive
Induce vomiting (emesis)—only if the pet is not having seizures—apomorphine, syrup of ipecac, or 3% hydrogen peroxide
Flush the stomach (gastric lavage)—This may be done but only before onset of vomiting and other clinical signs, or alternately, may be carried out if vomiting has been controlled, if drugs to induce vomiting are not effective, seizures are controlled, and an endotracheal tube is in place
Once vomiting is controlled—activated charcoal to attract and keep the remaining alkaloids in the gastrointestinal tract
Osmotic cathartic—sodium sulfate or sorbitol 70% promotes gastrointestinal elimination of chocolate
Hyperactivity and seizures—controlled with diazepam
Ventricular rapid heart rate (known as “tachycardia”) in dogs—lidocaine (without epinephrine); lidocaine is not recommended in cats
Serious abnormal heart rhythms (arrhythmias) that persist after medical treatment—metoprolol or propranolol; metoprolol is preferred but may be difficult to obtain
May use oral therapy once the pet is stable
Monitor electrocardiogram (ECG) and watch for hypotension (a possible complication to this treatment)
In rare cases of slow heart rate (known as “bradycardia”)—atropine may be used
Control of muscle rigidity may be obtained with methocarbamol
If response to diazepam inadequate—the veterinarian will consider phenobarbital or propofol
For refractory seizures—pentobarbital induced coma or general anesthetic may be needed; “refractory seizures” are seizures that do not respond or are not controlled with treatment
FOLLOW-UP CARE
Patient Monitoring
Electrocardiogram (ECG) to evaluate and monitor irregular heartbeats (arrhythmias)
Watch for mild to moderate kidney disease (known as “nephrosis”) in recovering pets
Preventions and Avoidance
Chocolate is among the 20 most common poisonings reported in recent literature, by small animal veterinary practices, animal poison control centers, and human poison control centers
Keep chocolate in a secure location, out of reach of pets
Do not use cocoa bean hull mulch in areas accessible to pets
Possible Complications
Pregnant pet—risk for abnormal development of fetus leading to birth defects of newborns
Nursing pets—overstimulation of nervous system in nursing newborns
Expected Course and Prognosis
Expected course—12–36 hours, depending on dosage of chocolate and effectiveness of decontamination and treatment
Successfully treated pets—usually recover completely
Prognosis—good if oral decontamination occurs within 2–4 hours of ingestion; guarded with advanced signs of seizures and irregular heartbeats (arrhythmias)
Key Points
Chocolate ingestion is hazardous to pets; if you suspect your pet has eaten chocolate, chocolate-containing products, or cocoa bean hull mulch, contact your veterinarian immediately
Describe the type of chocolate and amount of exposure to your veterinarian; take your pet to a veterinary hospital as a potential poisoning emergency
Chocolate is among the 20 most common poisonings reported in recent literature by small animal veterinary practices, animal poison control centers, and human poison control centers
Keep chocolate in a secure location, out of reach of pets
Be especially careful around holidays when chocolate products and candies are readily available
Do not use cocoa bean hull mulch in areas accessible to pets
If you suspect your dog has chocolate poisoning please contact us.
