What to do after ingestion
Vomiting, diarrhoea, reduced appetite, lethargy; retching or trouble swallowing suggests choking.
Stop feeding and monitor; contact a vet if signs persist or mouldy nuts were eaten.
Mycotoxins (in mouldy nuts)
Cats handle fatty foods poorly, so hazelnuts can cause digestive upset; whole nuts are a choking risk, the mycotoxin concern is the same, and cats gain nothing from them.
What to do after ingestion
Vomiting, diarrhoea, abdominal pain, poor appetite; a swallowed whole nut can cause retching, trouble swallowing or choking; mycotoxins can damage the liver.
A few plain unsalted hazelnuts usually need monitoring only; contact a vet immediately if vomiting or abdominal pain persists or mouldy nuts were eaten.
Mycotoxins (e.g. aflatoxins in mouldy nuts)
Hazelnuts are high in oil, so too many can cause vomiting and diarrhoea and may trigger pancreatitis; a whole nut can choke a small dog, and mouldy nuts may carry mycotoxins.
Nutrition
Per 100 g, edible portionData source:USDA FoodData Central · SR Legacy · Accessed on:2026-09-28
Cat · Safe feeding conditions
CautionNo additional condition notes for this food
Clinical and veterinary sources
Cats handle fatty foods poorly, so hazelnuts can cause digestive upset; whole nuts are a choking risk, the mycotoxin concern is the same, and cats gain nothing from them.
Mycotoxins (in mouldy nuts)
Vomiting, diarrhoea, reduced appetite, lethargy; retching or trouble swallowing suggests choking.
Stop feeding and monitor; contact a vet if signs persist or mouldy nuts were eaten.
Even crushed hazelnut should be a rare pinch rather than a regular cat treat.
Dog · Safe feeding conditions
CautionNo additional condition notes for this food
Clinical and veterinary sources
Hazelnuts are high in oil, so too many can cause vomiting and diarrhoea and may trigger pancreatitis; a whole nut can choke a small dog, and mouldy nuts may carry mycotoxins.
Mycotoxins (e.g. aflatoxins in mouldy nuts)
Vomiting, diarrhoea, abdominal pain, poor appetite; a swallowed whole nut can cause retching, trouble swallowing or choking; mycotoxins can damage the liver.
A few plain unsalted hazelnuts usually need monitoring only; contact a vet immediately if vomiting or abdominal pain persists or mouldy nuts were eaten.
Throw away any nuts that are mouldy, blackened or smell off; feeding is limited to shelled, unsalted plain hazelnuts given crushed and in very small amounts.
This website is for reference only and does not replace a licensed veterinarian. If your pet has eaten a suspected toxin or shows symptoms, contact a veterinarian or an emergency animal hospital immediately.
