When foreign debris or an irritating substance enters the eye, people often reach for contact lens solution, assuming that because it is safe for lenses, it must be safe for the eye. Contact lens solutions are not designed to be used as a general eye rinse or irrigation fluid, especially when the eye is already irritated or contains foreign material. Using these solutions directly in the eye for irrigation can introduce harsh chemicals and cause irritation, potentially worsening the initial problem.
The Immediate Answer: Why Contact Solution is Not Eye Rinse
Contact lens solutions, particularly multipurpose types, are complex chemical formulations created for cleaning, disinfecting, and storing lenses. They contain active ingredients like disinfectants and surfactants necessary to kill microorganisms and remove protein deposits. Preservatives, such as polyhexamethylene biguanide (PHMB) or polyquaternium-1 (Polyquad), are included to keep the solution sterile over time.
These disinfecting and cleaning agents are too harsh for the delicate tissue of the ocular surface. The eye’s natural tear film, which provides lubrication and protection, is easily disrupted by these active chemicals. The solution’s primary function is to sanitize a plastic lens, not to mimic the gentle chemistry of natural tears.
Hydrogen peroxide systems represent an even greater risk because they are potent disinfectants designed to be neutralized over several hours by a special disc or tablet. If un-neutralized hydrogen peroxide solution is poured directly into the eye, it can cause immediate and significant chemical trauma.
Potential Consequences of Rinsing with Contact Solution
Rinsing the eye with contact lens solution can lead to immediate discomfort. The disinfecting agents and preservatives often cause a stinging or burning sensation, accompanied by noticeable redness of the conjunctiva, indicating chemical irritation.
Repeated exposure can lead to toxic or chemical keratitis, which involves damage to the corneal epithelial cells. Preservatives like PHMB and Polyquad are known to bind to the corneal surface, causing superficial punctate staining. This staining indicates cellular damage and can compromise the integrity of the cornea, leading to increased dryness and sensitivity.
Un-neutralized hydrogen peroxide solution is the most hazardous, capable of causing a chemical burn on the cornea. This severe exposure can result in painful, temporary whitening of the eye tissue and requires immediate, prolonged irrigation to mitigate permanent damage.
Safe Alternatives for Eye Irrigation
When the eye needs rinsing due to debris, dust, or minor irritation, the safest alternatives are simple, sterile, and isotonic with the eye’s natural fluid. The ideal choice is a commercially prepared, sterile saline solution specifically labeled as an eye wash or for irrigation. This product is a simple mixture of purified water and 0.9% sodium chloride, matching the salt concentration of human tears and minimizing cellular disruption.
Over-the-counter artificial tears, or lubricating eye drops, are another gentle option for rewetting and flushing out small particles. These drops are formulated to be compatible with the eye’s natural environment and provide lubrication without the harsh disinfectants found in contact lens solutions.
In emergency situations where no sterile eye wash is available, clean, running tap water can be used for irrigation. While tap water is hypotonic and may cause slight initial discomfort, the need to flush out a harmful chemical or large debris outweighs this minor risk. The water should be lukewarm and applied in a gentle, continuous stream for several minutes to ensure thorough removal of the irritant.