General instructions for Refraction (eye exam)

Quick and painless test to accurately measure the prescription you need for glasses or contact lenses.

  • Definition: A quick and painless test to exactly measure the prescription you need for glasses or contact lenses.
  • Fasting: No fasting necessary. You can eat your usual food and drink water or liquids normally before coming to your appointment.
  • Medication: You should maintain and take your usual medication at the appropriate times, including the use of your daily eye drops if you have them. As always, any change or adjustment in your treatments should be discussed beforehand with your doctor.
  • Clothing and Accessories: You can wear the clothes you feel most comfortable in. There is absolutely no restriction on metals, jewelry, watches, or body accessories for this test.
  • Specific Requirements: It is very important that you take your current glasses or contact lenses to the consultation, plus your case and liquid if you use contact lenses, since the specialist will ask you to remove them to evaluate your vision naturally. In some cases (frequent in children, young people, or first prescriptions), the ophthalmologist or optometrist might need to apply drops to dilate the pupil and relax the eye muscle (refraction under cycloplegia). If so, we recommend being accompanied by an adult and wearing sunglasses, as it will not be safe for you to drive afterward.
  • Expected discomfort or pain from the test: The standard procedure is totally painless; you will only have to look through a machine (phoropter) or some test glasses while they change the lenses and ask you which ones you see better with, which only requires a bit of concentration. If dilating drops are applied, you will feel a slight sting that lasts a few seconds. After the drops, you will notice sensitivity to light (dazzle) and your near vision will be blurred for a few hours.