If you notice that your dog is coughing, this is generally not a cause for alarm. However, if you see that the dog coughs up blood, then the first you must do is head to the nearest veterinarian’s office – this is not the case of where you can try figure things out on your own. Do not wait to see if the cough goes away or if the blood stops or dries up.

When dogs cough up blood, it is a sign that something serious is going on internally. There are many different reasons why dogs could be coughing up blood, including: infection, internal damage and disease. Read on to find out more about the most common causes of dogs coughing up blood as well as potential next steps.

1. Heartworm

There are some infections that will cause your dog to cough up blood, and one of the most common is heartworm. If your pup has not been on a preventative or has missed some doses of the medication, they may have gotten heartworm, which is contracted from an infected mosquito bite. This requires an immediate trip to the vet. To determine whether or not your pooch has heartworm, your vet will perform a simple blood test.

Treatment for heartworm is extensive and expensive, but is necessary to save your dog’s life. The dog will receive a series of medication via injection over a period of time. While they are receiving injections, and during the time in between the injections, it is imperative for your pet to remain calm so they do not overexert themselves. Being active during heartworm treatment can be very harmful or even fatal to your dog.

2. Tuberculosis

Tuberculosis is a type of bacterial infection that can damage your dog’s respiratory system. If the animal has Tuberculosis, they may exhibit the following symptoms: coughing up blood in phlegm, weight loss, jaundice, increased thirst, and dehydration.

Even though Tuberculosis is rare in dogs, it can be transmitted through inhalation, so there is a possibility of them contracting it. There is also the possibility that dogs can infect humans if they are Tuberculosis-positive.

Unfortunately, there is no known treatment for Tuberculosis in dogs, so more than likely a dog infected with TB will have to be euthanized. The reason a dog would have to be euthanized is due to the risk of infecting humans. Those most as risk of contracting Tuberculosis from an infected dog are babies and young children.

3. Internal Damage

If your pet has suffered internal damage from a fight with another animal, vehicle accident, or other accident that has caused bodily harm and they are vomiting blood, they may have internal damage. You need to take your pet to the vet for testing.

Your veterinarian will most likely perform a physical examination. The various tests that the vet may run include: blood tests, urinalysis, x-ray, ultrasound, or CT scan. Treatment for internal damage will depend on the exact diagnosis, but may include: antibiotics/medication, surgery, and casting broken bones.

4. Disease

Pulmonary vascular disease could be the cause of your dog coughing up blood. Pulmonary vascular disease can be caused by many different things, including: anemia, pancreatitis, lung cancer, or inflammatory diseases. Each of these diseases has a range of other symptoms, ways to diagnose, and treatments that can be used.

5. Anemia

Anemia is the result of blood loss and/or a low blood iron count. Anemia-inciting processes include:

  • Blood loss due to internal or external injury
  • Immune system disease
  • Gastrointestinal bleeding due to disease or inflammation
  • Infectious diseases (like ones spread by ticks)
  • Toxin exposure
  • Lack of red blood cell production

Anemia diagnosis includes running a variety of tests: blood tests, urinalysis, x-rays, and CT scans. Treatment for anemia usually includes blood transfusions. If the anemia is not severe then a supplement may be prescribed and dietary changes may need to be made.

6. Pancreatitis

Pancreatitis in dogs is when the pancreas becomes inflamed, digestive enzymes that are normally inactive until they reach the small intestine become active in the pancreas instead—resulting in pain and swelling as the pancreas actually begins to digest itself. In addition to coughing up blood, symptoms for pancreatitis are:

  • Swollen abdomen
  • Abnormal posture; arching of the back
  • Diarrhea
  • Lethargy
  • Restlessness
  • Gagging

Treatment for pancreatitis includes medication, dietary modification, intravenous fluids, pain medication, anti-vomiting medication, and hospitalization in extreme cases.

7. Lung Cancer

Cancer in the dog's lungs can be caused by tumors that grow in or spread to the lungs. These are the following lung cancer symptoms in dogs (in addition to coughing up blood):

  • Pain
  • Difficulty breathing
  • Rapid breathing
  • Lethargy
  • Lack of appetite
  • Weight loss
  • Muscle loss
  • Fever
  • Fluid build up in the abdomen

Diagnosis is done through a panel of blood tests and x-rays. A true cure is not available for dogs; however, dogs can live comfortably with proper treatment. Treatment consists of removing the tumor(s) via surgery and prescription medication.

8. Inflammatory Diseases

Here Is What to Do If Your Dog Coughs Up BloodThere are chronic inflammatory diseases that can be controlled and treated; however, there are times where inflammatory diseases are serious and potentially life threatening. An inflammatory disease happens when an internal part of your dog becomes swollen, inflamed, and potentially infected.

Other symptoms related to inflammatory diseases to look out for are: swelling, redness, severe pain, stiffness, and seizures.

Diagnosis is done through physical examination, blood tests, x-rays, ultrasounds, and CT scans. Treatment depends on what exactly is inflamed, the severity of inflammation, and other factors. Medication and surgery are the two most common treatments.

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Rachael is a writer living in Los Angeles and an alum of UNC Chapel Hill. She has been a pet owner since the age of three and began dog-walking in 2015. Her nine-year-old Pug and best pal, Ellie, is the queen of sassy faces, marathon naps, and begging.