If you are using a fast pupil dilator, such as atropine, you will need to take one drop once every five minutes, four times in a row, and have your eye examined 20 minutes after the fourth drop. Fast pupil dilators are commonly used for the examination of patients between the ages of 10 and 18. If you are using a chronic dilator, atropine cream or gel, you will need to dilate your pupil at home, once in the morning and once in the evening, with a drop about the size of a green bean into the conjunctival sac, for three consecutive days, for a total of nine times, and then go to the hospital for an optometry.