Finding a lump in your neck can be alarming, particularly when you are not sure how long it has been there or why it appeared. Fortunately, most swollen lymph nodes are caused by benign conditions, particularly infections, and many shrink again as the underlying illness improves.¹˒²

Lymph nodes are small structures that form part of the lymphatic and immune systems. They help filter lymphatic fluid and participate in the body’s response to infections and other foreign material. When immune activity increases, nearby lymph nodes can temporarily enlarge, become tender, or feel more noticeable beneath the skin.¹

Swollen neck lymph nodes—also called cervical lymphadenopathy—commonly occur with colds, sore throats, ear infections, dental infections, tonsillitis, mononucleosis, and other infections involving the head and neck.¹˒³˒⁴

However, a lymph node that is progressively enlarging, hard, fixed in place, present for several weeks without improvement, located above the collarbone, or accompanied by unexplained weight loss, persistent fever, or drenching night sweats deserves medical evaluation.¹˒²

This guide explains what swollen lymph nodes in the neck mean, common causes, what features are more reassuring, what findings raise concern, and when you should choose primary care, urgent care, or the emergency department.

Medical disclaimer: This article is for general educational purposes only and cannot diagnose the cause of a neck lump or swollen lymph node. Persistent, enlarging, unexplained, or otherwise concerning lymph-node swelling should be evaluated by a qualified healthcare professional.

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What Are Lymph Nodes?

Lymph nodes are small collections of immune tissue located throughout the body. Common areas where people can sometimes feel them include the:

• Neck
• Under the jaw
• Behind the ears
• Armpits
• Groin

They act as part of the body’s immune surveillance system. When infection, inflammation, or another immune stimulus occurs nearby, lymph nodes may become more active and enlarge.¹

People frequently call these structures “swollen glands,” although lymph nodes are technically not glands.

The medical term for abnormal enlargement of lymph nodes is lymphadenopathy.

When inflammation or infection directly involves the lymph node itself, clinicians may use the term lymphadenitis. MedlinePlus notes that lymphadenitis commonly occurs in response to bacterial, viral, or fungal infection and may develop near an area of infection or inflammation.⁵

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Why Do Lymph Nodes in the Neck Swell?

The location of a swollen lymph node often reflects where the immune system is responding to a problem.

The neck contains lymph nodes that drain areas including the:

• Throat
• Tonsils
• Mouth
• Teeth and gums
• Ears
• Scalp
• Face
• Nasal passages

For that reason, infections involving these regions commonly cause swollen lymph nodes in the neck.¹

Common causes include:

• Viral upper respiratory infections
• Strep throat or other pharyngitis
• Tonsillitis
• Ear infections
• Dental infections
• Mononucleosis
• Skin or scalp infections
• Other viral illnesses

Less commonly, swollen neck lymph nodes may be associated with autoimmune conditions, certain medications, tuberculosis or other unusual infections, lymphoma, leukemia, or cancers involving the head and neck.¹˒²

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1. Colds and Viral Upper Respiratory Infections

A common cold is one of the most frequent situations in which people notice enlarged lymph nodes.

You may have:

• Runny nose
• Nasal congestion
• Mild sore throat
• Cough
• Fatigue
• Mild fever
• Tender lymph nodes along the neck

The lymph nodes enlarge because immune cells inside them are responding to infection.

In this setting, small tender nodes that appear at the same time as a viral illness and gradually shrink as the illness resolves are generally more reassuring than an unexplained mass that continues to enlarge.

A swollen lymph node may remain noticeable for several weeks after the tenderness improves, even after the original illness has resolved.¹

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2. Strep Throat and Tonsillitis

A bacterial throat infection such as group A streptococcal pharyngitis can cause swollen lymph nodes in the front of the neck.

CDC lists common strep-throat symptoms including:

• Rapid-onset sore throat
• Pain with swallowing
• Fever
• Red or swollen tonsils
• White patches or streaks of pus on the tonsils
• Swollen lymph nodes in the front of the neck⁴

Viruses cause most sore throats overall, so enlarged neck nodes plus a sore throat do not automatically mean antibiotics are needed. CDC notes that only a minority of adult sore throats are caused by group A strep.⁴

A healthcare professional may perform a rapid strep test or throat culture when appropriate. Also see sore throat and when to worry.

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3. Infectious Mononucleosis

Infectious mononucleosis, commonly called mono, is another classic cause of swollen lymph nodes in the neck.

It is most commonly caused by Epstein-Barr virus (EBV).³

Symptoms may include:

• Significant fatigue
• Fever
• Sore throat
• Headache
• Body aches
• Swollen lymph nodes in the neck or armpits
• Enlarged spleen or liver in some cases
• Rash³

Mono is particularly common among teenagers and young adults.

Most people improve over approximately two to four weeks, although fatigue can persist longer.³

Because the spleen can become enlarged during mono, contact sports and strenuous activities may need to be avoided until recovery to reduce the risk of splenic injury.³ Also see persistent fatigue and when to worry.

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4. Ear Infections

Ear infections can cause nearby lymph nodes to enlarge.

This is especially plausible when swollen nodes occur:

• Behind the ear
• Below the ear
• Along the upper neck

and are accompanied by:

• Ear pain
• Ear drainage
• Fever
• Hearing changes
• Recent respiratory symptoms

MedlinePlus includes ear infections among common causes of swollen lymph nodes.¹ Also see ear pain and common causes.

If the swelling behind the ear occurs with severe ear pain, marked redness, fever, or protrusion of the ear, prompt evaluation is appropriate because complications of ear infection can sometimes involve nearby structures.

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5. Dental and Gum Problems

An infected tooth or inflamed gums can produce swollen lymph nodes under the jaw or in the upper neck.

MedlinePlus specifically lists an abscessed or impacted tooth and gingivitis among causes of swollen lymph nodes.¹

Possible clues include:

• Toothache
• Gum swelling
• Facial swelling
• Pain when chewing
• Sensitivity to temperature
• Bad taste or drainage
• Tender lymph node under the jaw

A dental infection requires treatment of the dental source rather than simply treating the swollen node.

Rapid facial swelling, difficulty swallowing, drooling, voice changes, or difficulty breathing requires urgent or emergency evaluation.

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6. Skin and Scalp Infections

An infected wound, boil, inflamed hair follicle, or other skin infection on the scalp, face, or neck may trigger nearby lymph-node swelling.

Bacterial lymphadenitis can occur after skin infections, including infections involving organisms such as Streptococcus or Staphylococcus.⁵

Signs suggesting infection include:

• Tender lymph node
• Warmth
• Redness or discoloration
• Fever
• Nearby skin lesion
• Drainage
• Rapidly increasing swelling

A painful, inflamed lymph node may sometimes become infected enough to form an abscess, which can require antibiotics and occasionally drainage.

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7. Cat-Scratch Disease and Other Less Common Infections

Cat-scratch disease, caused by Bartonella, can produce enlarged lymph nodes near the site of a scratch or bite.

MedlinePlus lists cat-scratch disease among less common causes of lymphadenitis.⁵

Other infections that may cause lymph-node enlargement include:

• Tuberculosis
• Certain fungal infections
• HIV
• Toxoplasmosis
• Other systemic infections¹˒³˒⁵

Travel history, animal exposures, immune status, sexual history, and occupational exposures may therefore matter when the cause of lymphadenopathy is unclear.²

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Swollen Glands Under the Jaw

A lump under the jaw may represent an enlarged lymph node, but other structures are also present in this region.

Possible causes include:

• Throat infection
• Dental infection
• Mouth sores
• Salivary-gland problems
• Nearby skin infection
• Viral illness

The relationship to other symptoms provides useful clues.

For example:

Under-jaw swelling + toothache may suggest a dental source.

Under-jaw swelling + sore throat may suggest pharyngitis or tonsillitis.

Swelling worsened by eating may point toward a salivary-gland problem rather than a lymph node.

Persistent unexplained swelling under the jaw should be examined because not every neck lump is a lymph node.

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Swollen Lymph Node Behind the Ear

A swollen node behind the ear may occur with:

• Ear infection
• Scalp irritation
• Skin infection
• Viral illness
• Nearby inflammation

Look for symptoms such as:

• Ear pain
• Ear drainage
• Fever
• Scalp sores
• Rash
• Recent insect bite or skin injury

Also see rash and skin infection warning signs.

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What if Only One Side of My Neck Is Swollen?

Swollen lymph nodes do not have to occur symmetrically.

A localized infection may produce enlargement only on the side draining the affected area.

Examples include:

• One-sided dental infection
• Ear infection
• Skin infection
• Tonsillar inflammation
• Local throat infection

One-sided swelling is therefore not automatically a sign of cancer.

However, persistent unilateral lymphadenopathy without an obvious explanation deserves evaluation—particularly when the node is progressively enlarging, hard or fixed, or associated with persistent throat symptoms or other head-and-neck warning signs.²˒⁶

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Do Painful Lymph Nodes Mean Cancer?

Usually not.

MedlinePlus notes that lymph nodes that enlarge suddenly and are painful are more often related to infection or injury, whereas slower painless enlargement may warrant concern for tumors or cancer.¹

Tenderness is therefore somewhat reassuring when it occurs in an appropriate infectious context, but it is not a perfect diagnostic test.

A cancerous lymph node can occasionally be tender, and an infected node can sometimes be relatively painless.

The full clinical picture matters more than tenderness alone.

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How Can You Tell if a Swollen Lymph Node Could Be Cancerous?

This is one of the most common questions people search when they find a neck lump.

The most important answer is:

You cannot reliably diagnose or exclude cancer by feeling a lymph node at home.

Certain features may raise suspicion, but none confirm cancer without appropriate evaluation.

Features that deserve medical attention include:

• Persistent enlargement
• Progressive growth
• Hard consistency
• Nodes that feel matted or fixed to nearby tissues
• Supraclavicular location
• Unexplained fever
• Drenching night sweats
• Unintentional weight loss
• No clear infectious explanation
• Other persistent head or neck symptoms¹˒²˒⁶

AAFP notes that hard or matted lymph nodes, nodes larger than approximately 2 cm, and supraclavicular nodes can be more concerning for malignancy or granulomatous disease, although clinical interpretation depends on age and context.²

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Swollen Lymph Nodes and Lymphoma

Lymphoma is cancer involving lymphocytes, a type of immune-system cell.

Both Hodgkin and non-Hodgkin lymphoma can cause enlarged lymph nodes.

The National Cancer Institute lists signs and symptoms of Hodgkin lymphoma including:

• Painless swollen lymph nodes
• Unexplained fever
• Drenching night sweats
• Unexplained weight loss
• Fatigue⁷

These are sometimes called B symptoms, particularly fever, night sweats, and weight loss.

However, these symptoms are not specific to lymphoma. Infections and other illnesses can produce some of the same symptoms.⁷

The presence of one swollen lymph node does not mean someone has lymphoma.

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Could a Neck Lump Be a Head or Neck Cancer?

Rarely, an enlarged neck lymph node can represent spread from a cancer arising in the mouth, throat, voice box, or another head-and-neck structure.

NCI notes that head-and-neck cancers may cause:

• A persistent lump in the neck
• A mouth or throat sore that does not heal
• Persistent sore throat
• Difficulty swallowing
• Voice changes or persistent hoarseness
• Ear pain in certain presentations⁶

Major risk factors for many head-and-neck cancers include tobacco and alcohol exposure, while certain oropharyngeal cancers are associated with HPV.⁶

Persistent lymph-node enlargement along with ongoing throat, swallowing, voice, oral, or ear symptoms should therefore be professionally assessed.

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What About a Lymph Node Above the Collarbone?

A lymph node above the collarbone is called a supraclavicular lymph node.

This location deserves more attention than many other superficial nodes.

AAFP identifies supraclavicular lymphadenopathy as a location that raises greater concern for significant underlying disease, including malignancy, depending on the patient’s age and overall clinical picture.²

A new, persistent supraclavicular lump should be evaluated rather than simply monitored indefinitely at home.

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How Long Can a Swollen Lymph Node Last After an Infection?

A reactive lymph node may remain enlarged longer than the illness that triggered it.

MedlinePlus notes that tenderness may improve in a few days while a lymph node can take several weeks to return to its usual size.¹

This means:

“My cold is gone but I can still feel the node”

does not automatically indicate something serious.

What matters is the trend.

A node that is gradually shrinking is generally more reassuring than one that is:

• Increasing in size
• Becoming harder
• Persisting without improvement
• Appearing without any obvious infection
• Accompanied by systemic symptoms

MedlinePlus advises medical evaluation when lymph nodes fail to decrease after several weeks or continue enlarging.¹

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Should You Keep Touching a Swollen Lymph Node?

Repeatedly pressing, squeezing, or checking a lymph node can irritate surrounding tissue and make the area feel more tender.

It also becomes difficult to tell whether tenderness is from the original condition or repeated manipulation.

It is reasonable to monitor an uncomplicated small reactive node, but you do not need to palpate it repeatedly throughout the day.

If you are concerned about progression, note the general size and symptoms and arrange clinical evaluation instead of repeatedly manipulating it.

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When Should You Go to Urgent Care for Swollen Neck Lymph Nodes?

Urgent care can be appropriate when swollen neck nodes occur with a condition needing timely evaluation but the person is otherwise stable.

Examples include:

• Significant sore throat
• Fever
• Suspected strep throat
• Ear pain
• Dental or skin infection
• Tender enlarging node
• Possible bacterial lymphadenitis
• Persistent lymph-node swelling needing an initial evaluation

Urgent care may be able to perform:

• Vital signs
• Ear examination
• Throat examination
• Rapid strep testing
• Selected viral testing
• Basic laboratory testing
• Evaluation for nearby infection

Also see ear pain and when to seek care or sore throat warning signs.

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When Is a Swollen Neck Lump an Emergency?

Most swollen lymph nodes do not require the emergency department.

However, emergency evaluation may be appropriate if neck swelling is associated with:

• Difficulty breathing
• Significant difficulty swallowing
• Drooling or inability to handle saliva
• Rapidly expanding neck swelling
• Severe neck swelling with significant illness
• Signs of airway compromise
• Severe dehydration
• Confusion or altered mental status
• Significant facial or tongue swelling suggesting an allergic emergency

A swollen lymph node itself is rarely the emergency—the concern is whether the underlying process is threatening the airway, causing severe systemic illness, or rapidly progressing.

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When Should You Make a Routine Medical Appointment?

Schedule an appointment with primary care or another clinician if:

• The node persists for several weeks without getting smaller
• It keeps growing
• It feels hard, irregular, or fixed
• There is no obvious infection
• Multiple areas of lymph nodes are enlarged
• You have unexplained weight loss
• You experience drenching night sweats
• You have persistent fever
• You have unexplained fatigue
• You have a persistent neck mass along with swallowing, voice, throat, or ear symptoms¹˒²˒⁶

Generalized lymphadenopathy—enlarged lymph nodes in multiple nonadjacent regions—deserves broader evaluation because it is more likely to reflect a systemic process rather than one local infection.²

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How Do Healthcare Professionals Evaluate Swollen Lymph Nodes?

Evaluation begins with the history.

A clinician may ask:

• When did you first notice the lump?
• Is it painful?
• Has it changed size?
• Have you recently been sick?
• Do you have a sore throat?
• Do you have ear pain?
• Do you have dental symptoms?
• Have you had fever?
• Are you losing weight unintentionally?
• Do you have night sweats?
• Have you traveled recently?
• Have you had animal exposure?
• Have you started any new medications?
• Are lymph nodes enlarged elsewhere?

AAFP recommends considering node location and duration, associated symptoms, medical history, travel, animal exposures, medication use, recent vaccines, sexual history, and family history when evaluating lymphadenopathy.²

The physical examination may include:

• Size of the node
• Tenderness
• Mobility
• Consistency
• Whether nodes feel matted together
• Skin changes
• Location
• Examination of other lymph-node regions
• Ear, nose, throat, mouth, dental, and skin examination

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What Tests Might Be Needed?

Not every swollen lymph node requires testing.

A small tender cervical node accompanying an obvious viral illness may only need observation.

When the cause is uncertain, testing may include:

Complete Blood Count

A CBC can provide information about:

• White blood cells
• Red blood cells
• Platelets
• Patterns that may support infection or another hematologic process

MedlinePlus includes CBC with differential among potential tests used during evaluation of unexplained swollen lymph nodes.¹

Infection Testing

Depending on symptoms, testing may include:

• Strep test
• EBV/mononucleosis testing
• HIV testing
• Other targeted infectious testing

Testing should be based on clinical suspicion rather than ordering every possible infectious panel.

Imaging

Ultrasound, CT, or other imaging may sometimes be used when:

• The diagnosis is unclear
• The node is persistent or concerning
• An abscess is suspected
• Deeper neck structures need evaluation

Biopsy

A biopsy may be necessary when there is persistent unexplained lymphadenopathy or significant concern for malignancy or another disease requiring tissue diagnosis.

A biopsy does not mean cancer is certain. It means clinicians need a definitive tissue diagnosis because history, examination, laboratory testing, or imaging has not adequately explained the abnormal node.

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Can Antibiotics Make Swollen Lymph Nodes Go Away?

Only if the underlying problem is a bacterial infection that responds to the antibiotic.

Antibiotics do not treat:

• Viral infections
• Mono
• Reactive lymph nodes after a resolved infection
• Autoimmune disease
• Cancer
• Many other causes of lymphadenopathy

Strep throat, for example, is treated with antibiotics when confirmed or appropriately diagnosed.⁴

By contrast, infectious mononucleosis is usually viral and is managed primarily with supportive care.³

Do not use leftover antibiotics simply because a lymph node feels enlarged.

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Can Swollen Lymph Nodes Be Caused by Stress?

Stress itself is not a typical direct cause of lymph-node enlargement.

However, people under stress may:

• Notice normal body structures more often
• Repeatedly palpate the neck
• Experience concurrent viral illnesses
• Have symptoms related to sleep deprivation or immune stress

A persistently enlarged node should therefore be evaluated based on its actual features and associated symptoms rather than attributed solely to stress.

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Are Swollen Lymph Nodes Contagious?

The swollen node itself is not contagious.

However, the infection causing it may be.

For example:

• Strep throat can spread between people.⁴
• Infectious mononucleosis spreads mainly through bodily fluids, especially saliva.³
• Viral respiratory illnesses can spread through respiratory routes.

Therefore, whether precautions are needed depends on the underlying cause.

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Frequently Asked Questions

Why are the lymph nodes in my neck swollen?

Most commonly, neck lymph nodes enlarge because they are responding to an infection involving the throat, ears, mouth, teeth, skin, or respiratory tract.¹

Less commonly, autoimmune disease, unusual infections, medications, lymphoma, leukemia, or metastatic cancer can cause lymphadenopathy.¹˒²

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Are swollen glands in the neck usually serious?

No. Most lymphadenopathy encountered in primary care is benign, and infections are the most common cause.¹˒²

Persistent, enlarging, hard, fixed, supraclavicular, or otherwise unexplained nodes deserve evaluation.

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How long is too long for a swollen lymph node?

A reactive node may remain enlarged for several weeks after an infection.¹

If the node does not gradually decrease after several weeks, continues growing, or is associated with concerning symptoms, seek medical evaluation.

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Does a painful lymph node mean infection?

Painful nodes that appear suddenly are commonly associated with infection or injury.¹

However, pain alone cannot definitively establish the cause.

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Does a painless lymph node mean cancer?

No.

A painless node is not automatically cancerous.

However, slow painless enlargement without an obvious infection—particularly when the node is hard, fixed, persistent, supraclavicular, or associated with weight loss, fever, or night sweats—warrants medical evaluation.¹˒²˒⁷

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How can you tell if a swollen lymph node is cancerous?

You generally cannot tell for certain at home.

Features such as progressive enlargement, hard or matted consistency, supraclavicular location, persistence, and systemic symptoms can raise concern, but diagnosis may require laboratory testing, imaging, and sometimes biopsy.²

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What causes swollen glands under the jaw?

Common causes include:

• Sore throat
• Dental infection
• Mouth inflammation
• Viral illness
• Tonsillitis
• Nearby skin infection

Not every lump under the jaw is a lymph node, so persistent swelling should be examined.

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Why is only one lymph node swollen?

Localized infection can activate only the nodes draining that specific area.

One-sided swelling is therefore common with dental, throat, skin, and ear problems.

Persistent unexplained unilateral nodes still deserve evaluation.

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Should I go to urgent care for swollen lymph nodes?

Urgent care may be appropriate if the swollen nodes occur with fever, significant sore throat, suspected bacterial infection, ear pain, skin infection, or rapidly increasing tenderness.

A persistent but stable painless node is often better suited to primary care for a more complete evaluation and follow-up.

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The Bottom Line

Swollen lymph nodes in the neck are common and are usually caused by infection. Colds, sore throats, strep throat, ear infections, dental problems, mononucleosis, and skin infections can all cause nearby nodes to temporarily enlarge.¹˒³˒⁴

Features that are generally more reassuring include:

• Recent infection
• Tenderness
• Sudden appearance
• Gradual improvement
• Shrinking over time

Features that deserve medical evaluation include:

• Persistent or progressive enlargement
• Hard or fixed nodes
• Matted nodes
• Supraclavicular location
• Unexplained fever
• Drenching night sweats
• Unintentional weight loss
• Persistent throat, voice, swallowing, or ear symptoms¹˒²˒⁶

Most swollen neck lymph nodes are not cancer. However, you cannot reliably determine the cause by touch alone.

When a neck lump is new but clearly associated with a temporary infection, monitoring may be reasonable. When it is persistent, enlarging, unexplained, or associated with red-flag symptoms, an in-person evaluation is the safest next step. Also see swollen lymph nodes and when to worry.

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References

1. U.S. National Library of Medicine. Swollen lymph nodes. MedlinePlus Medical Encyclopedia. Updated January 14, 2026. Accessed August 11, 2026. MedlinePlus — Swollen Lymph Nodes
2. Falk N, et al. Lymphadenopathy: evaluation and differential diagnosis. American Family Physician. 2025. Accessed August 11, 2026. AAFP — Lymphadenopathy: Evaluation and Differential Diagnosis
3. Centers for Disease Control and Prevention. About infectious mononucleosis (mono). Updated May 9, 2024. Accessed August 11, 2026. CDC — Infectious Mononucleosis
4. Centers for Disease Control and Prevention. About strep throat. Updated January 15, 2026. Accessed August 11, 2026. CDC — Strep Throat
5. U.S. National Library of Medicine. Lymphadenitis. MedlinePlus Medical Encyclopedia. Updated May 12, 2025. Accessed August 11, 2026. MedlinePlus — Lymphadenitis
6. National Cancer Institute. Head and neck cancers. National Institutes of Health. Accessed August 11, 2026. NCI — Head and Neck Cancers
7. National Cancer Institute. Hodgkin lymphoma treatment (PDQ®) — Patient version. National Institutes of Health. Updated February 27, 2025. Accessed August 11, 2026. NCI — Hodgkin Lymphoma