Here are some IPS patches you can use to change the sprites and colours of Dr. Mario games to match the Game Boy sprites/palette. If you have trouble distinguishing pill colours this might be helpful for you.

If you don't know how to patch roms, google "Lunar IPS Tutorial"

Make sure that the ROM you are patching has the checksum listed.

NES (8181d696756578fc92e6c4c86da01904) - download

SNES (fea4d7179ed49b70de371c0d99e87842) - download - download with Y and B as flip buttons

N64 - (coming soon)

Thanks to Kaizoman666 for the code that changed the background and control scheme in SNES version!