Why are my lymph nodes swollen in my jaw?: A guide to common causes and when to see a doctor

September 30, 2025 •

4 min read

Over 70% of the body's lymph nodes are located in the head and neck, making swelling in these areas a common occurrence. Understanding why are my lymph nodes swollen in my jaw is often a matter of tracing the body's natural immune response back to its source.

Quick Summary

Swollen lymph nodes in the jaw or neck area most commonly signal a local infection, such as a cold, flu, dental issue, or sore throat, as the immune system works to filter out pathogens. Persistent swelling, accompanied by other specific symptoms, can indicate more serious, though rarer, underlying conditions like autoimmune diseases or cancer, requiring medical evaluation.

Key Points

Infection is the most common cause: The majority of cases of swollen jaw lymph nodes are caused by infections like colds, strep throat, or dental issues, and they resolve on their own.
Location indicates the problem: Swelling often occurs in nodes near the site of an infection, meaning issues in your mouth, head, or throat can affect the jaw nodes.
Duration is a key factor: If swelling lasts more than a few weeks or continues to grow, it warrants a doctor's visit to rule out more serious issues.
Consistency and tenderness matter: Nodes swollen from infection are usually soft, movable, and painful, while hard, fixed, or painless nodes can be more concerning and need evaluation.
Associated symptoms are important: Persistent fever, night sweats, or unexplained weight loss, when combined with swollen nodes, are signs to see a doctor immediately.

The lymphatic system: Your body's internal security network

The lymphatic system is a vital part of your body's immune defense, and lymph nodes are a key component. These small, bean-shaped glands filter a fluid called lymph, capturing germs, waste, and other foreign particles. When your body detects an invader, immune cells multiply rapidly within the nearest lymph nodes, causing them to swell. The submandibular lymph nodes, located under the jaw, and the cervical lymph nodes in the neck are often the first to react to issues in the head and oral cavity.

Common culprits behind swollen jaw lymph nodes

For most people, a swollen lymph node is a temporary, normal part of fighting off an infection. The swelling typically subsides as the illness resolves. The most frequent causes include:

Upper Respiratory Infections: Viruses like the common cold, flu, or mononucleosis can cause the lymph nodes in your neck and under your jaw to swell.
Dental Infections: An abscessed tooth, gingivitis, or an impacted tooth can trigger a strong immune response, leading to noticeably swollen nodes in the jaw area. Prompt dental care is necessary for these issues.
Throat Infections: Strep throat and tonsillitis are common bacterial infections that cause painful, tender swelling in the neck and jaw nodes.
Ear Infections: An infection in the ear can cause swelling in the nearby lymph nodes as the body works to fight the invading bacteria or virus.
Skin Infections: A localized skin infection or injury on the face or scalp can lead to swollen lymph nodes as a regional immune response.

Less common, but more serious, causes

While infection is the most likely cause, prolonged or unexplained swelling may signal a more complex health issue. These conditions are much rarer but should be evaluated by a healthcare professional, especially if swelling is persistent or accompanied by other symptoms.

Autoimmune Disorders: Conditions where the immune system mistakenly attacks healthy tissue, such as lupus or rheumatoid arthritis, can cause widespread lymph node swelling, including in the jaw.
Certain Medications: In rare cases, some medications, including certain antiseizure drugs and antimalarials, can trigger swollen lymph nodes as a side effect.
Cancer: Cancers can cause lymph nodes to swell, either by starting in the lymphatic system (lymphoma, leukemia) or by spreading from another part of the body. Cancers in the head and neck, oral cavity, or thyroid are examples where nodes under the jaw might be affected.

When to see a doctor for swollen lymph nodes

Most cases of swollen lymph nodes resolve on their own, but certain signs warrant a medical evaluation. Seek immediate medical care if you experience difficulty breathing or swallowing. Schedule an appointment if you notice any of the following:

Persistent swelling: The lymph nodes have been swollen for more than 2 to 4 weeks.
Growing larger: The size continues to increase rather than decrease over time.
Hardness or immobility: The nodes feel hard, rubbery, or are fixed in place and do not move when you press on them.
Systemic symptoms: You experience other unexplained symptoms such as fever, night sweats, or significant weight loss.
Unexplained swelling: There is no obvious nearby infection or illness to explain the swelling.

How are swollen lymph nodes diagnosed?

A doctor will determine the cause of your swollen lymph nodes through a physical exam and medical history review. Diagnostic steps often include:

Physical Examination: The doctor will check the lymph nodes for size, tenderness, and texture.
Blood Tests: These can help identify underlying infections or other systemic conditions.
Imaging Tests: CT scans or ultrasounds can provide more detailed images of the lymph nodes and surrounding areas.
Biopsy: For persistent or concerning nodes, a biopsy may be performed. This involves removing a small tissue sample for lab analysis to check for cancer or other diseases.

Comparison of infectious vs. cancerous lymph nodes


Feature	Typically Infectious Lymph Node	Typically Cancerous Lymph Node
Feel/Consistency	Soft, movable, and tender	Hard, rubbery, or fixed in place
Tenderness	Often painful or tender to the touch	Usually painless
Duration	Resolves within 2-4 weeks after infection subsides	Persists or progressively grows over time
Associated Symptoms	Often accompanied by fever, sore throat, or other signs of illness	May be accompanied by unexplained weight loss, night sweats, or fatigue
Onset	Tends to appear suddenly and acutely	Usually appears more slowly and without obvious cause

Home care for minor swelling

For swelling caused by a common infection, at-home care can help manage pain and tenderness while your body recovers.

Apply a Warm Compress: Place a warm, damp washcloth on the affected area for 10-15 minutes, several times a day.
Use Over-the-Counter Pain Relievers: Medications like ibuprofen (Advil) or acetaminophen (Tylenol) can help reduce pain and inflammation.
Get Adequate Rest: Allowing your body to rest is crucial for recovery from the underlying illness.
Stay Hydrated: Drinking plenty of fluids supports your body's immune function.

Note: This advice is for minor, infection-related swelling. It should not replace medical advice for persistent or concerning symptoms. An excellent resource for general health information, including details on swollen lymph nodes, is the Mayo Clinic.

Conclusion

Swollen lymph nodes under the jaw are a very common symptom, most often signaling that your immune system is actively fighting an infection in the nearby area, such as a cold, sore throat, or dental problem. While typically a temporary and harmless response, understanding the characteristics of the swelling—such as its tenderness, consistency, and duration—is important. Pay close attention to any additional symptoms, like fever or weight loss, and seek medical attention if the swelling persists, worsens, or is unexplained. Consulting a healthcare provider ensures an accurate diagnosis and proper management, giving you peace of mind and guiding appropriate treatment if needed.

Frequently Asked Questions

Yes, dental issues are a very common cause. Infections from an abscessed or impacted tooth, or inflammation from gingivitis, can cause the nearby lymph nodes under your jaw to swell as your immune system fights the infection.

For most infections, swollen lymph nodes will begin to decrease in size as the underlying illness resolves. Swelling typically subsides within 2 to 4 weeks. If the swelling lasts longer, gets bigger, or has no apparent cause, you should see a doctor.

Infectious nodes are usually soft, movable, and tender or painful to the touch. Cancerous nodes are often hard, rubbery, or fixed in place and are typically painless. A doctor's evaluation is necessary for an accurate diagnosis.

Yes, tenderness and pain are common symptoms of a swollen lymph node, particularly when the swelling is caused by an infection. Pain occurs because the node is actively working and inflamed.

Applying a warm compress to the area can help relieve tenderness and pain. Over-the-counter pain relievers like ibuprofen or acetaminophen can also be effective. Ensuring you get plenty of rest is also important.

You should see a doctor if your swollen lymph nodes persist for more than 2 to 4 weeks, continue to grow, feel hard and fixed, or are accompanied by fever, night sweats, or unexplained weight loss.

Yes, upper respiratory infections like the common cold or flu are among the most frequent causes of swollen lymph nodes in the neck and jaw. Your immune system mobilizes white blood cells to fight the virus, causing the nodes to enlarge.