Lymph Node Locations in Dogs

Lymph node locations are found at numerous sites on your dog’s body, including beneath his armpits, under his jaw, behind his knees, and in front of his shoulders. Let’s look at what lymph nodes do for your dog, what illnesses and conditions may affect them and what symptoms they may show in times of illness.

How Lymph Nodes Help Keep Your Dog Healthy

Lymph nodes or lymph glands are bean-shaped organs that are part of your dog’s lymphatic system. This system helps filter infections from your dog’s bloodstream and helps your dog’s body fight off disease. The lymphatic system also works with the cardiovascular system to maintain fluid balance throughout the dog's body, and it helps absorb digested fats in the small intestine.

The lymph nodes work with other parts of the lymphatic system, such as:

  • the bone marrow
  • the lymphatic vessels
  • the spleen 
  • the thymus gland

to identify and remove disease organisms and to create an immune response if health threats are detected.

As noted earlier, the lymph nodes in your dog’s body are concentrated in three primary areas: his neck, his armpits and his groin. In addition to the lymph node locations listed above, your dog also has lymph nodes in his chest and abdominal areas that cannot be easily felt on the outside of his body.

Illnesses that Affect a Dog’s Lymph Nodes

Lymph nodes can become enlarged as the result of many diseases, including:

  • allergies
  • cancer
  • infections
  • tooth abscesses

If a simple infection is the cause of the problem, the lymph nodes closest to the infection will become swollen as they help fight off the infection. The lymph nodes will return to their normal size once the infection has been treated.

Swollen lymph nodes can be a fairly common occurrence in your dog. This condition is called lymphadenopathy. Your dog’s other symptoms may depend on the location of the swollen lymph nodes. Dogs with sore throats, for instance, have swollen glands under their jaws, while dogs with infected paws may limp. Other symptoms may include appetite loss, breathing problems or lethargy.

In more serious conditions such as lymphoma or cancer of the lymph nodes, the nodes may need to be removed and follow-up treatments such as chemotherapy or radiation will be performed to restore your dog’s health.

How to Treat a Swollen Lymph Node

If you detect a swollen lymph node on your dog’s body, contact your veterinarian’s office for an appointment. The cause of the swollen node needs to be determined and treated to restore your dog’s health.

To find the cause of your dog’s swollen lymph node, your veterinarian will conduct a physical examination and perform laboratory tests, such as complete blood counts or urinanalysis. In some cases, he or she will insert a fine needle into the node to draw out a tissue sample for analysis, or the entire node may need to be removed and evaluated.

Once the disease is diagnosed, your veterinarian can begin treating your dog’s condition so he can become healthy again.