I had this - one cause is the infection of lymph nodes. Try not using deodrant for a few days up to a week and hopefully they will go. There are lymph nodes in your armpit and the deordrant traps vital vitamins, etc from not passing through the deodrant coating. It works amazingly. If they do not seek a doctor. But try this first. I am certain you will not regret it.
Hi, welcome to the forum, there are many reasons for lump in the arm pit. Some reasons are cyst, ganglion, infection, skin lesions, callus formation, injury, lipoma etc.
If it is infection, cyst, injury then antibiotics will help to subside the symptoms. Also you may undergo biopsy to rule out the cause. Treatment will in accordance with the cause. You may need minor incision or surgery to remove lump. I suggest you to consult surgeon. Take care and regards.
It could be a harmless cyst. My mother got them often from using antiperspirant with aluminum-they were removed with surgery and proved harmless, just hurt some and were annoying. I would get it checked out though.
If the lumps are UNDER the skin as opposed to being IN the skin you should see your doctor. Swollen lymph nodes under the skin can signify serious problems.
Take care of yourself.