Neck swelling can happen when lymph nodes or nearby tissues become inflamed, often during infections like the flu, a common cold, infectious mononucleosis (mono), an ear infection, or tonsillitis. In some cases, a swollen neck may also be linked to more serious conditions, including lymphoma.
Depending on the cause, swelling in the neck may occur with warmth, pain, redness, tenderness to touch, pus, or fever. Neck swelling may also appear as one or more lumps along the side of the neck, under the jaw, behind the ear, or in the back of the neck.
If neck swelling lasts more than three days or appears along with other symptoms, it is important to see a primary care provider to determine the cause and start the appropriate treatment.
Common causes
The main causes of neck swelling include:
1. Viral infections
Viral infections, such as the flu, a common cold, infectious mononucleosis, dengue, Zika, or cytomegalovirus, can cause neck swelling when the lymph nodes become enlarged. This swelling is part of the immune system’s normal response to fight the infection.
Swollen lymph nodes can appear anywhere in the neck and may be linked to other symptoms, such as sore throat, fever, or a general feeling of being unwell.
What to do: Rest and drink plenty of fluids, as neck swelling usually improves once the virus clears. In some cases, a healthcare provider may recommend pain relievers or fever reducers to help ease symptoms.
2. Bacterial infections
Some bacterial infections, such as an ear infection (otitis), tonsillitis, sinusitis, or pharyngitis, can cause swollen lymph nodes in the neck, behind the ear, under the jaw, or in the back of the neck, leading to neck swelling.
These infections are usually accompanied by other symptoms, such as fever, sore throat, trouble swallowing, ear pain, cough, facial pain, or even pus in the throat or ear.
What to do: Treatment should be guided by a primary care provider or an otolaryngologist (ENT). Antibiotics may be prescribed, depending on the type of infection.
3. Swollen or inflamed lymph nodes
Inflammation of the lymph nodes in the neck can cause swollen glands and lead to neck swelling. Along with swelling, symptoms may include pain, redness, skin tenderness, or fever.
Inflamed lymph nodes (also called cervical adenitis or cervical lymphadenitis) usually suggest inflammation or infection in the area. They can also occur due to autoimmune diseases, medication use, or cancers of the head and neck, including lymphoma.
What to do: Treatment for lymph node inflammation should be directed by a primary care provider and tailored to its underlying cause. Depending on the situation, options may include anti-inflammatory drugs, antibiotics for bacterial infections, antivirals for viral causes, corticosteroids to reduce swelling, or biologic therapies for autoimmune conditions.
If cancer is responsible, interventions often involve surgery to excise the affected lymph node or tumor, along with chemotherapy, radiation therapy, or both.
4. Thyroid changes
Some thyroid conditions, such as hypothyroidism or hyperthyroidism, can cause neck swelling known as a goiter. A goiter is an enlarged thyroid gland that can develop as the body tries to compensate for changes in thyroid hormone production.
What to do: See a primary care provider or an endocrinologist for evaluation. Imaging and lab tests may be ordered to confirm the diagnosis. Treatment depends on the cause of the goiter and may include iodine (when appropriate) or thyroid hormone replacement.
5. Mumps
Mumps (also called infectious parotitis) is caused by a virus in the Paramyxoviridae family. It affects the parotid, submandibular, and sublingual salivary glands, causing swelling of the face and especially the side of the neck.
Along with neck swelling, mumps can cause fever, pain with swallowing, and pain in the face and neck area.
What to do: Treatment focuses on symptom relief. A healthcare provider may recommend rest and medications to reduce discomfort, such as acetaminophen or ibuprofen.
The best prevention is the MMR (measles, mumps, and rubella) vaccine, which is given in childhood according to the recommended schedule.
6. Autoimmune diseases
Autoimmune diseases like lupus or rheumatoid arthritis disrupt the immune system, causing immune cells to accumulate in lymph nodes and leading to inflammation and swollen glands.
In these conditions, the swollen lymph nodes can appear in various parts of the body, not just the neck. Additional symptoms often include muscle pain, nausea, vomiting, and night sweats.
What to do: If an autoimmune disease is suspected, consult a primary care provider for evaluation and initial testing. Treatment can then begin if confirmed by the diagnosis.
7. Lymph node tuberculosis
Lymph node tuberculosis is an infectious disease caused by the bacterium Mycobacterium tuberculosis. It can cause swollen lymph nodes in the neck and chest, and may also appear in the back of the neck, armpits, or groin.
This type of tuberculosis is more common in people living with HIV and in women aged 20 to 40.
What to do: See a pulmonologist, infectious disease specialist, or primary care provider. Treatment may include antibiotics such as rifampin, isoniazid, and pyrazinamide for at least 6 months. Read more about tuberculosis treatment.
8. Cushing syndrome
Cushing syndrome is an endocrine condition caused by high cortisol levels in the blood. It can lead to rapid weight gain and fat buildup in the abdomen and face, which can make the neck look swollen.
This syndrome may be caused by long-term use of high-dose corticosteroids or by a pituitary gland tumor, for example. Learn more about Cushing syndrome.
What to do: See a primary care provider or endocrinologist for diagnosis. Treatment may include gradually lowering the corticosteroid dose or stopping it (under medical guidance).
If a pituitary tumor is present, surgery may be recommended to remove it, and in some cases chemotherapy or radiation therapy may be used.
9. Bacterial cellulitis
Bacterial cellulitis is a skin infection caused by bacteria such as Staphylococcus or Streptococcus. It can affect the neck after the skin is broken, such as from a cut, wound, or insect bite.
This infection usually causes swelling, pain, warmth, and redness in the area, and it may also be associated with fever, chills, and weakness.
What to do: Treatment should be guided by a primary care provider or infectious disease specialist. Antibiotics may be prescribed in pill form or, in more serious cases, be administered through an IV.
10. Lymphoma
A lump in the back of the neck can be caused by lymphoma, a type of cancer that affects lymph nodes. It can lead to swollen lymph nodes in the neck that do not go away after 1 to 2 months and continue to grow.
Other symptoms may also occur, such as fever, night sweats, extreme fatigue, and unexplained weight loss.
What to do: See a primary care provider, hematologist, or oncologist. Tests may be ordered, such as blood tests, a CT scan, or a PET-CT, to identify the type of lymphoma. Treatment is usually done with chemotherapy and/or radiation therapy.