Like most, if not all skin cancers start at your epidermis (The layer of skin that's most exposed to the sun) The cancer begins in your basal cells where they constantly push older skin cells toward the surface of your body.
Ritalin with other types of stimulants causes overactive eye movement. Ritalin belongs to a group of stimulants called Methylphenidate not only this but others such as cocaine,nicotine etc