Can eye color change?

Yes when young: Usually eye color is determined by about age 6 months. However, i had a patient whose eye color changed at age 6 years. I can't remember whether it was green to blue or vice versa.

Unusual: Eye color change in adults can signal a specific type of glaucoma. But very often, it seems that the eye color lightens, but this is due to haze in the cornea that can come with aging.

Pathological: Other answers can be from chronic inflammation that may be subclinical and destroy iris pigment making it appear lighter. If one is getting darker this can represent tumor enlarging either benign or malignant. This needs to be evaluated by an ophthalmologist.

No: The color of the eye can change with contact lenses, but physiologically no. It may change gradually with time.

Not much: There are a few eye drops that can darken the eyes, especially if they are hazel in color. There is no known way to lighten the eye color (except for contact lenses). Rarely, a cancer of the eye, severe inflammatiion or extreme pressure in the eye can cause a change in color.