Blood Loss in Cats – Internal and External

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  • Blood loss is a potentially life-threatening condition characterised by the loss of circulating blood either externally or internally. The blood has many functions including delivering nutrients and oxygen to the cells and transporting nitrogen from the cells to the lungs and out of the body.

    Blood loss can occur for several reasons, it may be external, which you will be able to see or internal, which is not always visible.

    External causes:

    • Cuts and wounds (such as bites), fractures, bleeding after delivering kittens, cat fleas, injuries sustained from a fall or a car accident, nosebleeds, gunshot wounds etc.

    Internal causes:

    • Trauma, blood clotting disorders, intestinal parasites such as hookworm.

    What are the signs of blood loss?

    Obviously, if the injury is external, you will see blood, however, internal injuries can be harder to pick.

    Common symptoms of blood loss include:

    • Bleeding from the mouth, nose, gums, anus. This can be due to an injury to the affected area. If bleeding occurs without any apparent damage and/or occurs from several parts of the body (such as the mouth, anus, gums etc), a blood clotting disorder is likely.
    • Small red dots (petechia) under the skin and mucous membranes.
    • Blood in the feces or vomit. This may be bright red (hematochezia), which indicates bleeding is occurring in the lower intestine (colon or rectum), or dark, tarry stools (melena), which is bleeding from the stomach or intestine. Melena is the more serious of the two.
    • Abdominal pain.
    • Vomiting blood (hematemesis) can indicate internal bleeding.
    • Symptoms associated with anemia include lethargy, weakness, pale gums, rapid breathing, loss of appetite.
    • Symptoms associated with shock include difficulty standing, confusion, panting, hypothermia (low body temperature), weak and rapid pulse, rapid but shallow breathing.

    Any visible wounds or trauma should be seen by a veterinarian immediately. If your cat has been involved in an accident, even if he appears to be well, you should also seek veterinary assistance as internal bleeding is a common result of trauma.


    If possible, try to stem the flow of blood by applying a clean gauze or sanitary pad to the affected area. Hands should be thoroughly washed before handling a cat with an injury. Take your cat to the veterinarian immediately.

    • Flush, clean and dress external wounds. Most fractures will need surgery to repair and fix the bone.
    • Flush, clean and add stitches to repair large wounds.
    • Diagnose and treat the cause of internal bleeding. This may require ultrasound and/or x-rays to determine the cause and the location of the bleeding.
    • Vitamin K for cats who have ingested rat poison. These poisons deplete the body of vitamin K, which is essential for the formation of certain clotting factors.
    • Supportive care may be necessary for the very sick cat, including oxygen and fluid therapy.
    • Anti-parasite medication to treat worms.

    Severe cases of blood loss may require a blood transfusion. This requires your cat’s blood group to be determined (there are three blood groups, A, B and AB), and the blood is taken from a suitable donor cat to be given via intravenous injection to your cat.


    • Julia Wilson, 'Cat World' Founder

      Julia Wilson is the founder of Cat-World, and has researched and written over 1,000 articles about cats. She is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. Full author bio