How many apple seeds are dangerous for a dog?

A medium dog weighing 20-30kg would need to chew and swallow several hundred to around a thousand seeds to approach the theoretical LD50 for hydrogen cyanide, and the true threshold is likely higher because each small apple seed carries well under a milligram of amygdalin. 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

Q: Can an apple core kill a dog?

Almost never from cyanide. A single apple core does not hold enough amygdalin to poison a dog: a 20kg dog would need to chew and fully metabolise several hundred seeds (the seeds of dozens of apples) to approach the roughly 2mg/kg lethal cyanide dose (Merck Veterinary Manual), and seeds swallowed whole pass through largely intact. The genuine, though still uncommon, way a core can seriously harm a dog is choking or gastrointestinal obstruction, and that risk is highest in dogs under 10kg. A healthy medium or large dog that swallowed one core is very unlikely to come to serious harm. Remove cores and seeds as a habit, watch for choking, repeated vomiting, refusal of water or no bowel movement for 24-48 hours, and call your vet or the ASPCA (888) 426-4435 if any appear.

Q: Are apple cores poisonous to dogs?

The seeds in the core contain amygdalin, a cyanogenic glycoside, so an apple core is mildly toxic in principle - but the quantity in one core is far below a dangerous dose for a dog, and whole seeds pass through undigested. The practical hazard of a core is physical, not chemical: it is a choking and obstruction risk, particularly for small dogs. Standard veterinary advice is to core and deseed apples before feeding, but a few accidentally swallowed seeds are not a poisoning emergency.

Updated April 2026

The short answer

Apple seeds contain amygdalin, which releases cyanide when chewed. However, a medium dog would need to chew many hundreds of seeds to approach a toxic dose - the seeds from dozens of apples. 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.

Can an apple core kill a dog?

Almost never from cyanide. One apple core does not hold enough amygdalin to poison a dog. A 20kg dog would need to chew and fully metabolise several hundred seeds - the seeds of dozens of apples - to approach the roughly 2mg/kg lethal cyanide dose (Merck Veterinary Manual), and seeds swallowed whole pass through largely intact. The genuine, though still uncommon, way a core can seriously harm a dog is choking or gastrointestinal obstruction, and that risk is highest in dogs under 10kg. A healthy medium or large dog that swallowed a single core is very unlikely to come to serious harm. Remove cores and seeds as a habit, and call your vet or the ASPCA at (888) 426-4435 if you see choking, repeated vomiting, refusal of water, or no bowel movement for 24-48 hours.

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). Bolarinwa et al. (2015) measured roughly 1 to 4 milligrams of amygdalin per gram of seed; an apple seed weighs only about 0.03g, so each seed holds well under a milligram of amygdalin and yields just a small fraction of a milligram of HCN even 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. On the deliberately cautious per-seed estimate used in the table below, that dog would need to chew and fully metabolise several hundred seeds - the seeds from dozens of apples - and because each seed really carries well under a milligram of amygdalin, the true threshold is higher still. Our dedicated seed cyanide math page shows the full per-weight calculation and sources.

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. Walkerville Vet (Australia) reached the same conclusion by a different route: they calculated that a medium dog would need to eat and fully chew roughly 85 grams of apple seeds - the seeds of around 200 apples - to reach a toxic dose, and concluded that sensible amounts of apple cores and seeds are harmless.

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

Based on amygdalin at 1 to 4 mg per gram of apple seed (Bolarinwa et al., 2015), the ~0.06 mg HCN per mg amygdalin conversion, and the ~2 mg/kg lethal HCN dose (Merck Veterinary Manual). Apple seeds are small (about 0.03g each), so per-seed content is well under a milligram; the seed counts here use a deliberately cautious per-seed estimate and are order-of-magnitude theoretical maxima assuming complete metabolisation of every chewed seed. Actual risk is far lower. See the seed cyanide math page for the full calculation.

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
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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 an apple core kill a dog?+

Almost never from cyanide. One apple core does not contain enough amygdalin to poison a dog - a 20kg dog would need to chew hundreds of seeds (the seeds of dozens of apples) to approach the ~2mg/kg lethal cyanide dose (Merck Veterinary Manual), and whole seeds pass through undigested. The real, though uncommon, danger is choking or gastrointestinal obstruction, which is highest in dogs under 10kg. A healthy medium or large dog that swallowed one core is very unlikely to be seriously harmed; call your vet or ASPCA Poison Control (888) 426-4435 if choking, repeated vomiting, refusal of water, or no bowel movement over 24-48 hours appears.

Are apple cores poisonous to dogs?+

The seeds contain amygdalin, a cyanogenic glycoside, so a core is mildly toxic in principle - but the amount in one core is far below a dangerous dose and whole seeds pass through undigested. The practical hazard is physical, not chemical: an apple core is a choking and obstruction risk, especially for small dogs. Core and deseed apples before feeding, but a few accidentally swallowed seeds are not a poisoning emergency.

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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