Trick or Treat: The Scary Side of Red-Eye Remover Drops
Red Eye is a visible eye condition in response to the dilation (enlarging) of blood vessels within the eye. Red Eye has many common causes, such as dryness, foreign body, allergies and more.
Many people are quick to use over-the-counter (OTC) eye drops, thinking it will solve the issue. OTC drops for red eye removal have derivatives of the medication imidazoline. Imidazoline works as a vasoconstrictor, which causes narrowing (constricting) of the blood vessels. Since the red eye appearance is a result of the dilation of blood vessels, constricting them will quickly reduce visible redness, but does not treat the actual cause of the blood vessel dilation.
With continued use of vasoconstrictors, the blood vessels which initially constricted will then reverse and expand larger than they were before the use of these drops. This effect is called “red eye rebound” or “rebound hyperemia.” Return of the Red Eye.
When you use red eye remover drops, you are temporarily reducing the visibility of redness, but you are not treating the actual cause of the irritation, inflammation or infection. Thus, the red eye cycle will continue. Best practice recommends finding the underlying cause of redness and treating it appropriately.
Some over-the-counter red eye remover brands contain the imidazoline, or a derivative, plus an antihistamine. Antihistamines work to block histamine, a chemical released in response to an allergen which would otherwise dilate blood vessels. OTC drops that contain both of these will relieve visible redness by constricting blood vessels, but they list eye irritation as a common side effect, which will perpetuate the cycle of red eye.