Seeing your dog sneeze blood clots is alarming. Even a small amount of blood can make the situation look serious, and blood clots often mean something is irritating, inflaming, or damaging the delicate tissues inside the nose.
We outline the common causes of a dog sneezing blood clots, what you can do at home, and when to seek veterinary help.
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Dog Sneezing Blood Clots: Why It Happens
A dog sneezing blood clots may have nasal inflammation, infection, trauma, foreign objects in the nose, dental disease, tumors, or clotting issues that affect the nasal passages. Blood clots form when bleeding has continued long enough for the blood to thicken, meaning the issue is rarely a simple one-time sneeze.
Dog Sneezing Blood Clots: Common Causes
Nasal Trauma or Irritation
Irritation from rough play, digging, rubbing the face, or forceful sneezing can rupture tiny blood vessels inside the nose.
A single burst vessel may cause a streak of blood, but repeated irritation can produce blood clots.
When a dog sneezes violently — especially during allergy flare-ups or after inhaling dust — the pressure inside the nasal cavity increases sharply, causing delicate capillaries to break.
Trauma-driven clots often form when the bleeding happens repeatedly or slowly enough that blood pools and dries before being expelled.
Dogs with sensitive noses, dry environments, or intense sniffing habits may be more prone to this.
The clots themselves are usually dark red or jelly-like, showing that the blood spent time in the nasal chamber before being pushed out during sneezing.
Read more: Dog Sneezing and Snorting (Understanding nasal irritation)
Foreign Object Lodged in the Nose
If your dog inhaled a piece of grass, a seed, a burr, or a small plant fragment, it can lodge deep inside the nasal cavity and cause irritation, infection, and bleeding.
When the object scratches or presses against the nasal lining, the tissue swells and bleeds, producing blood clots during sneezing.
Dogs experiencing this type of irritation often sneeze violently, paw at their face, rub their nose on the ground, or sneeze in repeated bursts.
The bleeding may appear on one side of the nose only, since foreign objects are typically trapped in a single nostril. These cases can escalate quickly because the trapped object may move deeper or cause increasing inflammation.
Nasal Infection
Both bacterial and fungal infections can cause chronic nasal inflammation, leading to bleeding and the formation of blood clots. Fungal infections — particularly Aspergillus — are well-known for causing nasal bleeding, discharge, sneezing, and discomfort in dogs.
These infections damage the lining of the nasal passages, eroding tissue and exposing fragile blood vessels.
Bacterial infections may start with mild cold-like symptoms but progress to thick discharge, swelling, and periodic bleeding. Blood clots appear when the bleeding occurs slowly or repeatedly inside the nasal cavity.
Dogs may show nasal congestion, noisy breathing, or facial tenderness as the inflammation worsens.
Nasal infections often require prompt veterinary care because they rarely improve on their own.
Nasal Mites
Nasal mites are microscopic parasites that live inside the nasal passages, causing intense itching, inflammation, and irritation.
Dogs with nasal mites often sneeze vigorously and repeatedly, causing bleeding that results in small or large clots.
Nasal mites spread easily between dogs through direct contact or shared bedding. Symptoms include sneezing fits, snorting, thick discharge, face rubbing, and sudden nasal discomfort.
These parasites burrow into the lining of the nasal cavity, making the tissue fragile and prone to bleeding whenever the dog sneezes.
Because the bleeding can persist, blood clots form and are expelled during sneezing episodes.
Dental Disease Affecting the Nasal Passage
The roots of a dog’s upper canine teeth and premolars sit very close to the nasal cavities. When dental infections or abscesses develop, the infection can break through into the nasal passage, causing bleeding, nasal discharge, and sneezing blood clots.
This type of nasal bleeding often develops slowly and is more common in older dogs or those with untreated dental decay.
Infections create pressure and inflammation that weaken the boundary between the mouth and nose. As a result, blood and pus may leak into the nasal cavity, producing thick clots when the dog sneezes.
Dogs with dental-related nasal bleeding may chew on one side, show bad breath, drool, or avoid hard foods.
Nasal Polyps or Tumors
Benign polyps, growths, and nasal tumors can cause a dog to sneeze blood clots due to structural disruption of the nasal passages.
As these growths enlarge, they interfere with airflow and irritate or erode blood vessels. Even a small amount of irritation can cause significant bleeding because the tumor tissue is fragile.
Older dogs are more prone to nasal tumors, and one-sided bleeding is common. Blood clots may be accompanied by chronic congestion, decreased airflow through one nostril, facial deformity, or noisy breathing.
While not all growths are cancerous, any persistent or repeated nasal bleeding warrants evaluation.
Coagulation or Bleeding Disorders
Some medical conditions reduce the dog’s ability to clot blood properly. Dogs on certain medications (like NSAIDs), dogs with poisoning (such as rat bait ingestion), or dogs with immune-related platelet disorders may bleed more easily from the nose.
When clotting is impaired, even mild nasal irritation produces prolonged bleeding that eventually forms clots.
These clots may appear thick, dark, and frequent. Dogs with clotting issues may also bruise easily, bleed from the gums, or show general signs of illness.
This cause is less common but extremely serious and requires urgent veterinary treatment.
Chronic Inflammation or Rhinitis
Long-term inflammation in the nasal passages — whether from allergies, irritants, or immune-related disorders — can weaken blood vessels and cause periodic sneezing of blood clots.
Chronic rhinitis creates constant irritation that causes the nasal lining to swell, dry, and crack. When inflammation persists, even a mild sneeze can dislodge a clot.
Dogs with chronic rhinitis may experience watery or mucus-filled discharge, reverse sneezing, noisy breathing, or persistent irritation. Blood clots may appear occasionally or frequently depending on the severity of inflammation.
Read more: Dog Sneezing and Wheezing (Causes explained)
What to Do If Your Dog Is Sneezing Blood Clots
First, stay calm and assess the situation. Check whether the bleeding comes from one nostril or both, as one-sided bleeding often suggests a foreign object, polyp, or localized infection, while two-sided bleeding may indicate irritation, systemic illness, or trauma.
Limit your dog’s activity temporarily. Physical exertion increases blood pressure and may worsen nasal bleeding.
Keep your dog calm and quiet while observing their breathing and behavior. Avoid touching or inserting anything into the dog’s nose — this can worsen the bleeding or push debris deeper.
Monitor for additional symptoms such as facial swelling, pawing at the nose, coughing, lethargy, difficulty breathing, or thick discharge. These signs can help identify the cause and urgency.
Remove your dog from dusty, grassy, or highly scented environments that may aggravate nasal irritation. If your dog recently sniffed tall grass or dug in dirt, gently wipe the muzzle to remove lingering particles.
Even if the bleeding stops quickly, blood clots indicate that irritation or trauma is occurring inside the nasal cavity. Because many causes require veterinary evaluation, it’s safest to schedule an exam promptly.
When to Call or Visit Your Vet
You should see your veterinarian promptly if your dog:
• Sneezes blood clots more than once.
• Has thick mucus, yellow discharge, or pus.
• Bleeds from only one nostril.
• Has swelling around the muzzle or under the eyes.
• Paw at the face or rubs their nose repeatedly.
• Shows decreased airflow through one nostril.
• Appears lethargic, weak, or loses appetite.
• Has bad breath, dental issues, or bloody saliva.
• Recently sniffed grass seeds or foreign material.
• Has bruising, gum bleeding, or signs of clotting problems.
Sneezing blood clots is not normal, and early diagnosis prevents complications.
Read more: Dog Sneezing Excessively (What’s behind it?)
Key Takeaway
A dog sneezing blood clots may have irritation, infection, nasal mites, dental disease, trauma, growths, or clotting issues that need attention.
While a single sneeze with a small clot may result from mild irritation, repeated or persistent episodes require veterinary evaluation. With timely care, most dogs recover fully and breathe comfortably again.