Lump on left arm. Hurts a bit?

Get it looked at. There are many things this could be. It depends on the history of how it started, how long has it been there, are there skin changes and exactly where is it. A quick visit with a md can likley give you the answer.

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Nocturnal left arm pain with a lump in the arm pit?

Infection? A lump in the armpit can be caused by several different things, one of which is infection. Do you notice lumps anywhere else on your body, particularly your neck or groin? Do you have any skin rashes or changes on your arm? Given your age, other causes of this lump and pain, although possible, are less likely. Read more...