How many apple seeds are dangerous for a dog?

A medium dog weighing 20-30kg would need to chew and swallow approximately 700-1,000 seeds to approach the theoretical LD50 for hydrogen cyanide. A single apple contains about 5-8 seeds. A few accidentally swallowed seeds - especially whole and unchewed - are almost certainly not dangerous.

What happens if a dog eats an apple core?

The main risks are choking (especially in small breeds) and gastrointestinal obstruction. Cyanide from seeds is a secondary concern and very rarely causes clinical poisoning from apple seeds alone. Monitor for vomiting, lethargy, inability to keep water down, abdominal pain, and no bowel movement for 24-48 hours. Small dogs or any dog with symptoms should be seen by a vet promptly.

Can Dogs Eat Apple Cores and Seeds? The Cyanide Question Answered

Updated April 2026

The short answer

Apple seeds contain amygdalin, which releases cyanide when chewed. However, a medium dog would need to chew approximately 700-1,000 seeds to approach a toxic dose - about 100-200 apples worth. The real danger of apple cores is choking and gastrointestinal obstruction, not cyanide poisoning. Remove cores and seeds as a habit, but do not panic if your dog swallowed a few seeds whole.

The science: amygdalin and cyanide

Apple seeds contain a cyanogenic glycoside called amygdalin. When chewed and mixed with enzymes in the gut, amygdalin metabolises to hydrogen cyanide (HCN). Each apple seed contains approximately 0.6mg of amygdalin, yielding roughly 0.042mg of HCN when fully metabolised.

The canine lethal dose for hydrogen cyanide is approximately 2mg per kilogram of body weight (Merck Veterinary Manual). For a 20kg Labrador, that is 40mg HCN total. At 0.042mg per seed, that dog would need to chew and fully metabolise approximately 952 seeds - more than 100 average apples worth.

Critically: seeds swallowed whole and unchewed pass through the digestive system largely intact because the amygdalin is locked inside the seed coat. The theoretical risk applies only to chewed seeds. In practice, clinical cyanide poisoning in dogs from apple seeds alone is exceptionally rare. Walkersville Vet (Australia) noted in their clinical review that they had not treated a single case of cyanide toxicity from apple seed ingestion in over a decade of practice.

The mainstream veterinary guidance - remove seeds as a habit - is still correct and sensible. But the fear should be proportionate: a dog eating a few seeds from one apple is almost certainly fine. A small dog who compulsively chews and swallows many seeds over time is a different matter.

Theoretical seed count to reach toxic dose (chewed seeds)

Dog weight	Seeds to toxic dose (chewed)	Clinical note
5kg (Chihuahua)	~120	Very small dog - err on the side of caution
10kg (Pug)	~240	Still call vet if symptoms appear
20kg (Beagle)	~480	Monitor 24-48h after single core
30kg (Labrador)	~720	Large dose of seeds unlikely from one apple
40kg (German Shepherd)	~960	Would require multiple apples worth of seeds, chewed
60kg (Great Dane)	~1,440	Theoretical LD50 from seeds essentially unreachable from normal apple ingestion

Data based on: amygdalin 0.6mg/seed, HCN yield 0.042mg/seed, canine LD50 2mg/kg (Merck Vet Manual). These are theoretical maximums assuming complete metabolisation of every seed. Actual risk is lower.

The core: a more real danger than cyanide

The hard apple core is a genuine hazard for very different reasons. It is dense, fibrous, and resistant to easy chewing - which means it can:

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Choking hazard: Small dogs can lodge a core piece in the oropharynx or oesophagus. Signs: gagging, pawing at mouth, retching, distress, blue-tinged gums. This is an emergency - do not wait.
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GI obstruction: A swallowed core can obstruct the pylorus (stomach exit) or small intestine, especially in dogs under 10kg. Signs develop over 6-24 hours: repeated vomiting, inability to keep water down, abdominal pain, lethargy, no bowel movement.
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Stem splinters: The stem can splinter and puncture the soft palate, tonsils, or oesophageal wall. Remove stems even if you leave the flesh.

My dog ate a whole apple with the core - what now?

Small dog (under 10kg) + whole core

Call your vet or poison control now. Do not wait for symptoms. High obstruction risk.

Medium/large dog (10-40kg) + whole core

Monitor closely for 24-48h. Watch for vomiting, lethargy, refusal of water, no bowel movement. If any symptom appears, call vet.

Large dog (40kg+) + one apple core

Low risk but monitor overnight. One bowel movement confirming passage is reassuring.

Any dog + multiple cores

Call vet regardless of size. Volume matters.

Symptoms of cyanide poisoning from seeds (rare)

If a dog chewed a very large quantity of seeds (hypothetically), cyanide symptoms would appear within 15-45 minutes of ingestion:

Dilated pupils
Bright red (cherry-red) gums and mucous membranes
Rapid panting or laboured breathing
Excessive drooling
Seizures in severe cases
Collapse

If you see these symptoms after any apple seed ingestion, call (888) 426-4435 (ASPCA Poison Control) immediately. Speed is critical with cyanide.

Frequently asked questions

Can puppies eat apple seeds?+

Puppies should be treated with extra caution. Their smaller body weight means any toxic threshold is lower, and they are less likely to chew with enough mechanical force to fully break down seeds. More importantly, the choking and obstruction risk from any core piece is higher in puppies. Remove all seeds and core before serving any apple to a puppy.

What about crabapple seeds?+

Crabapples belong to the same Malus family as domestic apples. Their seeds contain the same amygdalin compound. The same risk profile applies: casual ingestion of a few seeds is unlikely to cause clinical poisoning, but the fruit is much smaller so the seed-to-flesh ratio is higher. If your dog ate crabapples, apply the same decision tree as above based on size.

Should I make myself vomit my dog?+

Do not induce vomiting without explicit instruction from a vet or poison control. Vomiting can cause aspiration pneumonia if done incorrectly, and in some poisoning scenarios (caustics, objects that can lodge in the oesophagus on the way back up) is actively harmful. Always call poison control first.

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