Using melanin and its derivative, analog and precursor for treating and preventing being described for eye disease, illness and situation. Melanin or derivative, analog or its precursor, such as synthesis of melanin or natural melanin are applied to eyes and pass through part or injection. It includes hyperemia by method described herein that one kind of example ophthalmology disease, illness and situation, which can treat or prevent, and hickie, corneal vessels generate and the keratoconus of cornea.
