Will msm and alpha-arbutin eye drops lighten my eye color? if not what medication can i use to permanently kill the melanin in my eyes.

Melanin will never : Be killed. It's a permanent fixture in the eye. In fact, certain eyrdrops can actually turn the color of the eyes from blue or green to brown permanently. So you have nothing to worry about. Your iris color helps protect your eyes from too much sun, and creates the pupil opening to being light and images in. So you want to keep it healthy, and not kill it.