Swollen glands are lymph nodes that have grown larger than normal, usually because your immune system is actively fighting off an infection. Lymph nodes are small, bean-shaped structures scattered throughout your body that filter fluid and trap germs, damaged cells, and other harmful substances. When they’re working hard, they fill with extra immune cells and can swell to a size you can feel under your skin. Most of the time, this is a sign your body is doing exactly what it should.
What Lymph Nodes Actually Do
Your body contains hundreds of lymph nodes connected by a network of thin vessels. Fluid that leaks out of your blood vessels, called lymph, travels through these vessels and passes through the nodes on its way back to your bloodstream. That fluid carries proteins, nutrients, and also germs or damaged cells picked up from your tissues.
Inside each node, immune cells work to identify and destroy anything harmful. Small particles are processed by one set of immune cells deep inside the node, while larger invaders like bacteria are intercepted by a different group closer to the surface. When your body detects an infection nearby, the lymph node ramps up its activity: it produces more immune cells, traps more debris, and swells as a result. During inflammation, the vessels feeding the node also widen, bringing in even more fluid and immune cells from the bloodstream.
Where You Can Feel Them
Lymph nodes exist throughout your body, but you can only feel them in a few places where they sit close to the skin’s surface. The most common spots are along the sides and back of your neck, under your jaw, in your armpits, and in your groin. These are the areas people typically notice first when fighting a cold, sore throat, or skin infection. Nodes deeper in the chest or abdomen can also swell but aren’t detectable by touch.
The location of swelling often gives a clue about what’s going on. Swollen nodes in the neck commonly accompany throat or ear infections. Nodes in the armpit may react to a skin infection on your hand or arm. Groin nodes often respond to infections or injuries in the legs or genital area.
The Most Common Causes
Infections are by far the most frequent reason for swollen glands. Common culprits include strep throat, ear infections, mononucleosis, infected teeth, measles, skin infections like cellulitis, and wound infections. Essentially, any infection can trigger nearby lymph nodes to swell. In children, the cause is benign more than 80% of the time, with viral and bacterial infections topping the list.
Less commonly, swollen glands can result from autoimmune conditions like lupus, where the immune system mistakenly attacks healthy tissue and keeps nodes chronically activated. Certain cancers, particularly lymphoma and leukemia, can also cause lymph node swelling. These are far less common than infections but worth being aware of, especially when swelling persists without an obvious cause.
What They Feel Like
Swollen lymph nodes from infection are typically tender to the touch, soft or slightly firm, and move freely when you press on them. The tenderness comes from pressure building inside the node’s outer capsule as it fills with immune cells. They might range from the size of a pea to the size of a cherry or even larger during an active infection.
The texture and feel of a swollen node can reveal a lot about what’s behind it. Nodes that feel firm and rubbery, move easily under the skin, and aren’t particularly painful may suggest lymphoma. Nodes that feel very hard, almost stone-like, are painless, and seem stuck to the tissue around them are more concerning for cancer that has spread from another part of the body. When a group of nodes clump together so they feel like one mass, this can point to either a serious infection like tuberculosis or a malignancy.
Nodes related to infection or autoimmune conditions generally slide around freely when you push on them. Nodes linked to cancer are more often fixed in place, attached to the skin or deeper tissues so they don’t move.
How Long Swelling Lasts
Swollen glands caused by a typical infection usually shrink back to normal within one to two weeks. Even after the infection clears, nodes can stay slightly enlarged for a bit longer as the immune response winds down. If your nodes are still getting bigger after a week, or haven’t gone down at all after two weeks, that’s a good reason to have them checked.
Signs That Need Attention
Most swollen glands are nothing to worry about. But certain features set apart the cases that deserve a closer look:
- Painless swelling that persists or grows. Infections usually hurt. Painless nodes that keep enlarging over weeks are more suspicious.
- Hard, fixed nodes. A node that feels rock-hard and doesn’t move under the skin warrants evaluation.
- Night sweats, unexplained weight loss, or persistent fevers. These systemic symptoms alongside swollen nodes can point to lymphoma or another serious condition.
- Swelling in multiple areas at once. Nodes enlarging in the neck, armpits, and groin simultaneously may indicate a body-wide process rather than a local infection.
- Size beyond 1.5 centimeters. Nodes larger than about 1.5 cm (roughly the width of your thumbnail) on imaging are considered potentially significant and may need further evaluation.
How Persistent Swelling Is Evaluated
If swollen glands don’t resolve on their own, a doctor will typically start by examining the nodes and asking about other symptoms, recent illnesses, and travel history. Blood tests can check for signs of infection or immune system problems. An ultrasound can measure the node precisely and show its internal structure, helping distinguish between a reactive (infection-fighting) node and one that looks abnormal.
When imaging raises questions, the next step is often a biopsy, where a small sample of the node is removed with a needle or through a minor surgical procedure. This allows a pathologist to look at the cells directly and determine whether the cause is infection, inflammation, or something more serious. Nodes under 1 cm in their shortest dimension are generally considered normal and rarely need biopsy unless other red flags are present.