As responsible pet owners, ensuring the health and wellbeing of our dogs stands paramount amongst our duties. Whilst dogs have evolved alongside humans for millennia, their digestive systems and metabolic processes differ significantly from our own. Consequently, many foods that are perfectly safe—indeed, beneficial—for human consumption can pose serious health risks to our four-legged friends. This comprehensive guide aims to illuminate the various foodstuffs that may prove toxic to dogs, detailing the potential consequences of ingestion and providing guidance on preventative measures and emergency responses.
Common Household Foods Toxic to Dogs
According to Blue Cross (2), the most common toxic foods to dogs are:
1. Chocolate and Caffeine Products
Perhaps the most widely recognised canine toxin, chocolate contains methylxanthines—specifically theobromine and caffeine—which dogs cannot metabolise efficiently. Dark chocolate and baking chocolate pose the greatest risk due to their higher concentration of these compounds. Symptoms of chocolate toxicity may include:
- Vomiting and diarrhoea
- Increased thirst and urination
- Restlessness and hyperactivity
- Elevated heart rate and blood pressure
- Muscle tremors
- Seizures
- In severe cases, cardiac failure
Similarly, coffee, tea, energy drinks and other caffeine-containing products present comparable risks. The severity of symptoms typically correlates with the quantity consumed and the size of the dog.
2. Allium Family Vegetables
Members of the allium family—onions (3), garlic (3), leeks and chives (1)—contain compounds that can damage canine red blood cells, potentially resulting in haemolytic anaemia (1). Whilst all dogs may suffer adverse effects from these vegetables, certain breeds, including Japanese breeds such as Akitas and Shiba Inus, demonstrate heightened sensitivity.
Notably, these vegetables remain harmful in all forms—raw, cooked, powdered or dehydrated. Symptoms of allium toxicity may not manifest immediately, potentially emerging several days after consumption:
- Lethargy and weakness
- Pale gums
- Elevated heart and respiratory rates
- Vomiting and diarrhoea
- Dark-coloured urine
3. Grapes and Raisins
Grapes and their dehydrated counterparts, raisins, can induce acute kidney failure in dogs (4). Most concerning is the unpredictable nature of this toxicity—whilst some dogs may consume grapes without apparent ill effect, others may suffer severe reactions from minimal quantities. Currants and sultanas present similar risks.
Symptoms of grape or raisin toxicity may include:
- Vomiting and diarrhoea
- Lethargy
- Decreased appetite
- Abdominal pain
- Decreased urination or cessation of urination
- Halitosis (bad breath)
4. Xylitol
This sugar substitute, commonly found in sugar-free products such as chewing gum, sweets, baked goods, peanut butter and oral hygiene products, can induce a rapid release of insulin in dogs, resulting in hypoglycaemia (low blood sugar). Additionally, xylitol may cause liver failure (1).
Symptoms of xylitol toxicity may develop rapidly, potentially within 30 minutes of ingestion:
- Vomiting
- Loss of coordination
- Lethargy
- Seizures
- Liver failure (presenting as jaundice, vomiting, lethargy)
Even small quantities of xylitol can prove lethal to dogs, underscoring the importance of vigilant supervision.
5. Alcohol
Ethanol, found in alcoholic beverages and certain food products, affects dogs more profoundly than humans. Additionally, dogs may encounter alcohol in unexpected forms, including fermenting dough, alcoholic sauces and certain desserts. Symptoms of alcohol toxicity may include:
- Depression of the central nervous system
- Lack of coordination
- Vomiting
- Elevated body temperature
- Decreased heart rate
- Seizures
- Respiratory depression
- Coma
6. High-Risk Fruits and Nuts
- Macadamia Nuts (3,4): Macadamia nuts can cause temporary hindlimb weakness, hyperthermia and vomiting in dogs. Whilst the precise toxic compound remains unidentified, symptoms generally resolve without permanent damage. Nevertheless, consumption warrants veterinary attention.
- Avocados (3,4): Whilst the flesh of avocados presents minimal risk to most dogs, the plant's leaves, bark, seeds and skin contain persin, a compound toxic to various animals. The pit presents an additional hazard as a potential choking or intestinal obstruction risk.
- Cherries (5): Cherry pits contain cyanide, which can be released if the pit is crushed or chewed. Additionally, the pits pose choking and obstruction risks.
7. Animal Products and Proteins
- Fish with Thiaminase: Certain fish, including carp, herring, smelt and trout, contain thiaminase, an enzyme that destroys thiamine (vitamin B1). Regular consumption of raw fish containing thiaminase may result in thiamine deficiency (7), manifesting as neurological symptoms.
- Bones and Fat Trimmings: Cooked bones, particularly from poultry, may splinter when chewed, potentially causing oral injuries, choking or gastrointestinal perforations (8). Fat trimmings can induce pancreatitis, a painful and potentially life-threatening inflammation of the pancreas.
8. Plants and Herbs Commonly Found in Kitchens
- Yeast Dough: Uncooked yeast dough can expand in a dog's warm stomach, potentially causing bloat or gastric dilatation-volvulus, a life-threatening emergency. Furthermore, the fermentation process produces ethanol, potentially resulting in alcohol toxicity (9).
- Certain Herbs and Spices: Nutmeg contains myristicin, which can cause hallucinations, disorientation and increased heart rate in dogs (10). Similarly, certain herbs, including pennyroyal, tea tree and wormwood, contain compounds toxic to canines.
9. Dairy Products and Salts
- Dairy Products: Whilst not universally toxic, many dogs lack sufficient lactase, the enzyme necessary for lactose digestion. Consequently, dairy consumption may result in gastrointestinal distress, including diarrhoea and vomiting (11).
-
Salt: Excessive sodium consumption can induce sodium ion poisoning in dogs, manifesting as:
- Vomiting
- Diarrhoea
- Tremors
- Elevated body temperature
- Seizures
- In severe cases, death
Emergency Response to Suspected Poisoning
Should you suspect your dog has consumed a toxic substance, prompt action is imperative:
- Remove the dog from the substance's vicinity to prevent further ingestion
- Collect relevant information, including:
- The suspected toxic substance
- Approximate quantity consumed
- Time of ingestion
- Your dog's weight
- Any observed symptoms
- Contact your veterinarian or an emergency veterinary service immediately. In the UK, the Veterinary Poisons Information Service provides 24-hour guidance to veterinary professionals
- Do not induce vomiting unless explicitly directed to do so by a veterinary professional, as this may exacerbate certain poisonings
- Transport your dog to the veterinary clinic promptly if advised
Supporting Digestive Health in Dogs
Maintaining optimal digestive health can assist dogs in processing and eliminating small quantities of harmful substances before significant absorption occurs. Supplements such as CaniNectar, with its natural enzymes, B vitamins, antioxidants and minerals, can support digestive efficiency and promote a balanced gut microbiome, potentially enhancing the body's natural detoxification processes and improving overall gastrointestinal resilience. Such supplementation, whilst not a substitute for preventing toxic ingestion, may form part of a comprehensive approach to canine wellbeing.
Conclusion
As our dogs rely upon us for their safety and wellbeing, understanding and preventing access to potentially harmful foodstuffs represents a fundamental aspect of responsible pet ownership. By maintaining awareness of common canine toxins, implementing preventative measures and responding promptly to suspected poisoning incidents, we can significantly reduce the risk of food-related harm to our beloved pets.
If you are interested in learning about foods that are safe and beneficial for your dog, we invite you to read our blog, "Safe Human Foods for Dogs: A Comprehensive Guide", which provides detailed information on nutritious human foods that can be safely shared.
References
- Burke, A. (2024, July 5). Can Dogs Eat Peanut Butter? American Kennel Club.
- Blue Cross. (2024, January 10). Poisonous foods for dogs.
- 4 Paws Veterinary Hospital. (2024, March 8). Onion and Garlic Toxicities in Pets.
- American Kennel Club. (2024, March 26). Fruits and Vegetables Dogs Can or Can't Eat.
- Ripley, K. (2024, August 14). Can Dogs Eat Cherries? American Kennel Club.
- Arford, K. (2024, March 14). Can Dogs Eat Eggs? American Kennel Club.
- Edwards, K. A., Randall, E. A., Wolfe, P. C., Angert, E. R., & Kraft, C. E. (2023). Dietary factors potentially impacting thiaminase I-mediated thiamine deficiency. Scientific reports, 13(1), 7008.
- Mitchell, S. (2024, May 30). What To Do if Your Dog Ate a Chicken Bone. Pet MD.
- Riley, E. (2021, May 27). Yeast Dough Dangers in Pets. Veterinary Partner.
- Reisen, J. (2022, November 29). Can Dogs Eat Nutmeg? American Kennel Club.
- Mitchell, S. (2024, January 10). Can Dogs Drink Milk? Pet MD.
Share:
Safe Human Foods for Dogs: A Comprehensive Guide