I’ve seen some dreadful destructive tutorials for removing red-eye in Photoshop. This is the easy, safe way to do it.
This method is for both Photoshop and Elements. It works well a lot of the time, but there might be some cases where it falls short.
Thanks to Sonya C for letting me use this small snippet of her photo for this tutorial:
Just add a Hue/Saturation adjustment layer, go to Reds, and move the Lightness slider all the way to -100:
Then invert the mask and paint on the pupil only:
For blue and green eyes, no particular precision should be necessary when masking. For brown eyes, a little more care might be required, but it shouldn’t be too painstaking.