Armpits and deodorant

Hi I have a question - Whenever I wear deodorant for a couple days in a row I get an itchy rash in my armpits. I tried different kinds: Gillette, speed stick, even my moms because thought maybe the men's deodorant was to
harsh. Has anybody else had this problem? Is there a kind I should try? My mom said she looked for ones for sensitive skin but there was none.
I don't even know if I need to bother with using it. I smelt the pits on my shirts after I wear them and they aren't bad. It's mostly just that everybody else does after pe class so I thought I should.
so I guess I'm asking if I should wear it and if so what kind won't give me a rash?
thankd