What Causes a Rash in Your Armpit? An armpit rash is more common than you might think. Your armpits probably come into contact with more chemicals each day than most other parts of your body. Don’t be ...

Medically reviewed by Theresa Marko, PT, DPT, MS Key Takeaways Armpit pain can come from injuries, infections, or swollen lymph nodes.  To diagnose armpit pain, doctors may use lab tests, physical ...