Eye whitening drops are a liquid medication applied for the purpose of relieving irritated eyes and reducing bloodshot eyes. These drops are available over the counter, or as prescription eye drops when a stronger solution or additional eye medication additive is required. This eye whitening medication contains vasoconstrictor, a drug that causes the tiny blood vessels of the eye to shrink, giving the appearance of whiter eyes. The eye drops are applied to the outer surface of the eye.
For many individuals, red eyes are an unsightly and uncomfortable condition. Too much work, lack of sleep, eye strain, allergies and other maladies can cause the tiny blood vessels on the surface of the sclera to bulge. The sclera is the creamy white surface of the eye that surrounds the iris and supports the moist, gelatinous outer surface of the eyeball, called the conjunctiva. Normally, the sclera is white with a slightly bluish cast, and the blood vessels are so small that they are not noticeable. Red eye occurs when the blood vessels of the white portion of the eyeball bulge with blood.
Some eye whitening drops also contain antihistamines, or lubricants to relieve the swelling, itching and redness from allergies. Most commercially-available eye whitening drops contain only vasoconstrictors, manufactured for the sole purpose of reducing the unsightly blood vessels of the eye. Eye whitening drops are ineffective against infections, allergies, conjunctivitis or other bacterial or viral diseases.
Physicians and manufacturers warn against individuals using eye drops for extended periods of time, because a "rebound" type of red eye disorder may occur. Rebound swelling is the over-reaction of the blood vessels after a long period of constriction. Frequent, prolonged use of eye whitening drops may worsen the condition. In very rare but severe cases, vision loss may occur.
The blood vessels in the eyes supply oxygen and nutrients to the various parts of the eye, particularly the cornea and limbus. Vasoconstrictors as found in eye drops cause the vessels to shrink, reducing blood flow to the parts of the eye. The eye, starved for blood, strains for nourishment. When the whitening effects of the vasoconstrictors wear off, the engorged blood vessels relax and shoot out larger quantities of blood. Blood vessels then appear even larger, exacerbating the red eye problem and creating a vicious cycle of more and more treatment.