What is the difference between Lycra spandex and spandex? Is there latex in either of these?

I recently purchased some new bras. I now have a rash. Material makes skin contact over entire breast area, rash is limited to only a portion of this area.What is the difference between Lycra spandex and spandex? Is there latex in either of these?
Lycra and Spandex are both name-brands of similar material. Both are long-strand polymers and both are synthetic. I do not believe that there is any latex in spandex or lycra. If you have had some sort of reaction, I suggest washing the garments. The dyes in the fabric could be irratating your skin. Also, neither Lycra nor Spandex are absorbant, so it could be that your sweat is trapped inside the garment.What is the difference between Lycra spandex and spandex? Is there latex in either of these?
Ouch, that's gotta hurt, just go bra-less.
lycra spandex is supoose to be more breakthable. as for your rash, try cotton