Swollen Lymph Nodes in Armpit: 10 Causes (& What to Do)
A swollen lymph node in the armpit can emerge due to local inflammation or infections, like folliculitis, boils or lymphadenitis. It may also be a result of autoimmune diseases, vaccine reactions or cancer, and is associated with pain, discomfort, fever and redness. Learn more about the causes of reactive lymph nodes.