The most common cause of swollen lymph nodes in the neck is an infection, usually from a virus or bacteria.

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There are about 600 lymph nodes in your body, and most of them are located in your neck. A lymph node is part of your body’s defense system. A body fluid that comes out of your blood, called lymph, runs through your lymph nodes. The job of the lymph node is to recognize any foreign substances in the lymph, like a virus, bacteria, or cancer cell. Once recognized, the node uses white blood cells to recognize and attack the foreign invader. This causes the lymph node to swell up, called lymphadenopathy.

Lymph nodes in your neck are located in front of your ear (preauricular), under your chin (submental), under your jaw (sub mandibular), down the side of your neck (anterior cervical), down the back of your neck (posterior cervical), and just above your collar bone (supraclavicular). There are many possible causes of the swollen nodes. Doctors do a history and physical, exam to determine the cause. They may also order lab tests, imaging studies, and in some cases a biopsy to determine the cause and best treatment.

What causes swollen lymph nodes in the neck?

The most common cause is an infection, usually from a virus or bacteria. White blood cell cancers and cancers of the head and neck, or cancers from other parts of the body are uncommon causes. Overall, less than one percent of lymph nodes are cancer, but after age 40 the number goes up to four percent.

The location of the node or nodes is a good clue to the cause. Preauricular lymph nodes are usually due to a scalp or ear infection. Submental and submandibular nodes may be caused by an oral infection, tonsillitis, infected tooth, mononucleosis, and rarely head and neck cancers. Supraclavicular nodes may be caused by lung or stomach cancer.

After infections, other causes can include autoimmune disorders like rheumatoid arthritis or systemic lupus erythematosus. Several medications can cause lymphadenitis including some antibiotics, seizure medications, blood pressure, and gout medications. Cancers that cause neck nodes include head and neck cancers, white blood cell cancers, and cancers that spread to lymph nodes from other parts of the body.

How to treat swollen lymph nodes in the neck naturally

You should not treat swollen lymph nodes at home unless the cause is a typical cold virus. If you are being treated by your doctor for an infection like tonsillitis or an infected tooth, home care can include a warm compress and an over-the-counter pain and fever medication like Tylenol or Advil. There are no herbal supplements or other home treatments that are recommended.

When to worry about swollen lymph nodes in the neck

Call your doctor about swollen lymph nodes in your neck if a node or nodes:

• Have no obvious cause
• Have not gone away within two weeks
• Are red, warm, and tender or draining pus or fluid
• Are painless but hard and hard to move under your skin
• Occur with other symptoms like persistent fever, night sweats, weight loss, or fatigue