Why Is This Lump Here? Why Your Lymph Nodes Are Swelling & Medically-Approved Next Steps

Finding a lump—especially in your neck, under your jaw, in your armpit, or near your groin—can be unsettling. In many cases, that lump is a swollen lymph node. The good news? Most swollen lymph nodes are not dangerous and are actually a sign your immune system is doing its job.

Still, it's important to understand what lymph nodes are, why they swell, and when you should speak to a doctor.

---

What Are Lymph Nodes?

Lymph nodes are small, bean-shaped glands that are part of your immune system. They are located throughout your body, but you can usually feel them in areas like:

• The sides of the neck
• Under the jaw
• Behind the ears
• Under the arms (armpits)
• In the groin

They act as filters. Lymph nodes trap viruses, bacteria, and other harmful substances. When they detect a problem, they activate immune cells to fight it. This immune response is often what causes swelling.

---

Why Do Lymph Nodes Swell?

Swollen lymph nodes—also called lymphadenopathy—usually mean your body is responding to something. The most common causes are not serious.

1. Infections (Most Common Cause)

This is by far the leading reason lymph nodes swell.

Common infections include:

• Colds and flu
• Strep throat
• Sinus infections
• Ear infections
• Dental infections
• Skin infections
• Mononucleosis
• COVID-19

For example, if you have a sore throat, the lymph nodes in your neck may swell because they're fighting the infection.

In these cases, lymph nodes:

• Feel tender
• Are movable under the skin
• Swell quickly
• Often shrink back down within 2–3 weeks

---

2. Local Inflammation or Injury

If you have:

• A cut on your arm
• A pimple or skin infection
• A shaving nick

The nearby lymph nodes may enlarge as part of the immune response.

---

3. Immune System Conditions

Autoimmune diseases can cause persistent or widespread lymph node swelling. Examples include:

• Rheumatoid arthritis
• Lupus

In these cases, the immune system is overactive and can trigger enlarged lymph nodes.

---

4. Certain Medications

Some medications can cause lymph node swelling as a side effect. While uncommon, it's something doctors consider during evaluation.

---

5. Cancer (Less Common, But Important to Rule Out)

Although most swollen lymph nodes are benign, some can be linked to cancer. This includes:

• Lymphoma (cancer of the lymphatic system)
• Leukemia
• Metastatic cancer (cancer that spreads from another part of the body)

Cancer-related lymph nodes tend to:

• Be hard or firm
• Not move easily
• Continue growing
• Persist longer than 4 weeks
• Occur without infection symptoms
• Be accompanied by unexplained weight loss, night sweats, or persistent fever

It's important not to panic—these cases are far less common than infection-related swelling. But they do require medical evaluation.

---

Where the Lump Is Matters

The location of swollen lymph nodes can provide helpful clues.

Swollen Lymph Nodes in the Neck

Commonly linked to:

• Upper respiratory infections
• Throat infections
• Dental issues

If you've discovered swelling in this area and want to understand what might be causing it, you can use a free AI-powered symptom checker for a lump in the neck to get personalized insights and guidance on whether you should see a doctor.

---

Swollen Lymph Nodes in the Armpit

Often related to:

• Skin irritation
• Shaving
• Infections in the arm or breast
• Recent vaccinations

---

Swollen Lymph Nodes in the Groin

May be associated with:

• Leg or foot infections
• Skin wounds
• Sexually transmitted infections

---

What Do Normal vs. Concerning Lymph Nodes Feel Like?

Here's a helpful comparison:

Usually Less Concerning:

• Soft or slightly rubbery
• Tender to touch
• Moveable
• Associated with cold or infection symptoms
• Shrink within a few weeks

More Concerning:

• Hard, like a rock
• Fixed in place
• Painless but steadily growing
• Larger than 1–2 centimeters
• Persist longer than 4 weeks
• Accompanied by night sweats, fatigue, or weight loss

If you notice concerning features, don't delay evaluation.

---

How Long Should Swollen Lymph Nodes Last?

For most infections:

• Swelling improves within 2–3 weeks
• Sometimes nodes remain slightly enlarged even after the infection clears

If a lymph node:

• Continues growing
• Doesn't shrink after 4 weeks
• Appears without a clear cause

It's time to speak to a doctor.

---

What Doctors Do to Evaluate Swollen Lymph Nodes

If you seek medical care, your provider may:

1. Perform a Physical Exam

They'll check:

• Size
• Texture
• Location
• Tenderness
• Whether other lymph nodes are enlarged

2. Ask About Symptoms

Important questions include:

• Recent illness?
• Fever?
• Night sweats?
• Unexplained weight loss?
• Travel history?
• Animal exposure?
• Recent vaccinations?

3. Order Tests (If Needed)

Depending on findings, they may recommend:

• Blood tests
• Ultrasound imaging
• CT scan
• Biopsy (in rare cases)

Most people do not need extensive testing. Doctors often recommend short-term monitoring first.

---

What You Can Do at Home

If your swollen lymph nodes are likely from a mild infection:

• Rest
• Stay hydrated
• Use over-the-counter pain relievers (as directed)
• Apply a warm compress

Avoid constantly pressing or checking the lump—this can make it more irritated and prolong swelling.

---

When to Speak to a Doctor Immediately

Seek prompt medical care if you experience:

• Difficulty breathing or swallowing
• Rapidly enlarging swelling
• High fever that doesn't improve
• Severe pain
• Hard, fixed lymph nodes
• Night sweats soaking through clothes
• Unexplained weight loss
• Swelling lasting longer than 4 weeks

These symptoms don't automatically mean something serious—but they do require evaluation.

---

Should You Worry?

In most cases, swollen lymph nodes are:

• Temporary
• Infection-related
• A sign your immune system is working

However, ignoring persistent or unusual swelling isn't wise. Paying attention without panicking is the right balance.

If you're unsure, starting with a structured tool like a free AI symptom checker for a lump in the neck can help clarify next steps before you schedule an appointment.

---

The Bottom Line

Lymph nodes swell because your immune system is responding to something. Most of the time, that "something" is a minor infection.

Here's what to remember:

• Swollen lymph nodes are common.
• Infections are the most likely cause.
• Location and feel matter.
• Most resolve within a few weeks.
• Persistent, hard, or growing lymph nodes need medical evaluation.

If anything about your symptoms feels concerning—or if you're experiencing warning signs—speak to a doctor promptly. Early evaluation is always better than waiting when it comes to potentially serious conditions.

Your body often gives you signals when something needs attention. Understanding lymph nodes helps you respond calmly, confidently, and appropriately.