Sounds very Outer Limits-esque, but I don't recall that specific episode. It's certainly at least an easy interpolation from many Outer Limits episodes, though.
On the other hand, let's aim for the juiced up immune systems portrayed in one of the Star Trek series. It gets so powerful it can reject acquaintances.
I have always been a huge fan of the show but sitting here trying to figure out what you specifically are referencing?
I can't remember which series it was, though.