Why weren't Kryponians getting sick from kryptonite, like Superman?

Did Kryptonite make S-man sick or just normal?

Because they were on their home planet of Krypton. Had they gone elsewhere, they would have gotten sick like Superman if they were exposed to it.

I think Rojo got it right. Kryptonite was the one substance which rendered the residents of Krypton equivalent to earthlings. Although I seem to remember episodes in the comics with Superman appearing weak and exhausted (sort of like an asthmatic) when exposed to the stuff.

Due to their Sun’s explosion, the particles of Krypton have a very specific radiation, which weakens Superman.

Yeah, but it supposedly just took away his superpowers. I never understood why it always seemed like he would die any minute if he couldn’t get away from it.