Swollen lymph nodes usually occur as a result of exposure to bacteria or viruses. When swollen lymph nodes are caused by an infection, this is known as lymphadenitis (lim-fad-uh-NIE-tis). Rarely, swollen lymph nodes are caused by cancer.

Your lymph nodes, also called lymph glands, play a vital role in your body's ability to fight off infections. They function as filters, trapping viruses, bacteria and other causes of illnesses before they can infect other parts of your body. Common areas where you might notice swollen lymph nodes include your neck, under your chin, in your armpits and in your groin.

In some cases, the passage of time and warm compresses may be all you need to treat swollen lymph nodes. Treatment of lymphadenitis depends on the cause.

Oct. 26, 2016
  1. Longo DL, et al., eds. Enlargement of lymph nodes and spleen. In: Harrison's Principles of Internal Medicine. 19th ed. New York, N.Y.: The McGraw-Hill Companies; 2015. http://www.accessmedicine.com. Accessed July 25, 2016.
  2. Fletcher RH. Evaluation of peripheral lymphadenopathy in adults. http://www.uptodate.com/home. Accessed July 25, 2016.
  3. Lymphadenitis. Merck Manual Professional Version. http://www.merckmanuals.com/professional/dermatologic_disorders/bacterial_skin_infections/lymphadenitis.html. Accessed July 25, 2016.
  4. Motyckova G, et al. Why does my patient have lymphadenopathy or splenomegaly? Hematology and Oncology Clinics of North America. 2012;26:395.
  5. AskMayoExpert. Lymphadenopathy. Mayo Foundation for Medical Education and Research, Rochester, Minn.; 2016.
  6. Dorland's Illustrated Medical Dictionary. 32nd ed. Philadelphia, Pa.: W.B. Saunders; 2011. http://dorlands.com/index.jsp. Accessed July 25, 2016.
  7. Litin SC (expert opinion). Mayo Clinic, Rochester, Minn. July 27, 2016.