Causes Of Blood From The Nose

Updated March 26, 2021

Nosebleeds in dogs are rare and worth taking seriously. Unlike humans, dogs almost never get an occasional harmless nosebleed. Causes include injuries, foreign bodies, infections, clotting problems and tumours.

At the end I’ll tell you how you and your vet can work out which one it is.


The most common cause of nosebleeds is trauma. If a dog hits their nose hard, such as on a fence or when trying to catch the ball, it may cause bleeding. Similarly, a dog that pokes his nose under fences on walks is eventually going to find something or someone on the other side.

If the cause is trauma, it should stop within a few minutes. You can help the bleeding stop by calming your dog so they don’t rub, shake or paw at their face.

Foreign Bodies

Another common cause is the grass seed or foxtail. Thes are small grass awns that get sniffed up by dogs especially in Spring and Summer. As you can see from the video, once they get up there, they won’t just come out.

Dogs start with a yellow discharge from one nostril that becomes blood-tinged the longer the grass seed remains in the nose. This is usually accompanied by violent sneezing.


Although kennel cough is often listed as a cause of bleeding from the nose, I haven’t personally seen this. If it occurs, it would be secondary to prolonged sneezing and have a mixed discharge with pus.

Fungal infections are much rarer but can cause a blood-tinged discharge from one or both nostrils. There may also be an external deformity of the nose or neurological signs. The most common agents are Aspergillus and Cryptococcus, and are very difficult to eliminate.

Clotting Problems

Many dogs with problems that interfere with blood clotting will bleed from the nose. Causes include:

Clues that it’s a clotting defect are the presence of bleeding elsewhere such as bruises or swellings, blood patches on the gums or blood in the stool. Coagulation disturbances are extremely serious and require immediate veterinary attention.

High Blood Pressure

High blood pressure is unusual in dogs, but when it happens you may see nosebleeds. If a dog has hypertension, there’s usually an underlying disease.

Nasal Tumours

If a nosebleed is caused by a tumour it’s bad news. 80% of these tumours are malignant, and most of the time there’s little that can be done except palliative therapy. Fractionated radiation therapy usually offers the best prolongation of life.

Thankfully, tumours are a reasonably uncommon cause of blood from the nose. When they happen, the blood is usually in small quantities from just one nostril.

How To Diagnose Nasal Bleeding

So what do you do if your dog has a blood nose? Firstly, remember that if there’s any chance of a clotting problem, you need to find a vet straight away.

For other problems, you can help your vet by checking two things:

  1. Touch a white tissue to the nose. This should tell you if a discharge is coming from one or both nostrils and its colour.
  2. Hold a cold mirror up to the nose and look at the condensation pattern. This will tell you if one or both nostrils are blocked.

Your vet will usually eliminate the causes in a series of steps as long as there is time to do so. These will depend on the history and physical exam, but will often include:

  • Blood tests and blood pressure measurement
  • A treatment trial with anti-inflammatories and/or antibiotics
  • An anaesthetic to look for a foreign body sometimes followed by a nasal flush
  • Cytology of the discharge to look for fungi
  • Nasal or dental x-rays
  • A biopsy if there is abnormal tissue
  • A CT scan

Related: Causes Of Sneezing & Runny Nose In Dogs

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By Andrew Spanner BVSc(Hons) MVetStud, a vet in Adelaide, Australia. Meet his team here. The information provided here is not intended to be used as a substitute for going to the vet. If your pet is unwell, please seek veterinary attention.

3 Replies to “Causes Of Blood From The Nose”

  1. Hi we had a reversal for speclist. She did a scope and flush his nose .and put on meds.the did bloods. But still he is bleeding cant find the cause.

  2. Hi my dog was bleeding from his nose i took him vet it stopped abt a week now stated again.he is on meds wt must I do

    1. Hi Cynthia. The cause should be one of those mentioned this article so please go back to your vet as we don’t always find the answer the first time.

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