Red kryptonite returns in Adventure Comics #255 (October 1958). Maybe the writers forgot or ignored the “red kryptonite is 10 times as powerful as green kryptonite” story from a few months and wanted to tell a different story. This time a “Martian” brings a fragment of red kryptonite to Earth and it splits Superboy into two beings: his super-powered self and an evil powerless version of Clark Kent, leading to a battle where Superboy is attacked by his super-robots:
Ultimately the over-use of the “multiple switch” ends up causing an explosion that destroys “evil Clark”. This second effect of red kryptonite eventually leads to the easy route for writers to tell wacky one-off stories of Superman/Superboy transforming in weird ways.