When you realize you are out of contact lens solution, the immediate temptation is to reach for a common household liquid, but this decision carries significant risks to eye health. Contact lens solution is a medical device specifically formulated to clean, disinfect, and hydrate lenses, and safely substituting it is nearly impossible. Improper storage, even for a short time, can turn your contact lenses into breeding grounds for harmful microorganisms, potentially leading to severe eye infections and vision damage. For this reason, the safest and most recommended action is always to remove your lenses and wear glasses until you can obtain a proper, commercially prepared solution.
Why Water and Homemade Solutions are Dangerous
Never use tap water, bottled water, saliva, or any homemade saline mixture to store or rinse contact lenses. Tap water, even if it is considered safe for drinking, contains microorganisms that can cause serious eye infections. This includes the presence of the parasite Acanthamoeba, which can lead to a rare but devastating condition known as Acanthamoeba keratitis. This infection attacks the cornea, is extremely painful, and can result in permanent vision loss.
Homemade saline solutions, often made by mixing salt and boiled water, are also unsafe because they are not sterile and lack the necessary disinfecting agents. While boiling water sterilizes the water itself, the salt, mixing container, and any non-sterile measuring tools can easily introduce contaminants. These mixtures also lack preservatives, making them vulnerable to rapid bacterial growth. Saliva contains bacteria from the mouth that can transfer directly to the lens and eye, causing severe infections.
The Only Acceptable Short-Term Substitutes
In an emergency, if a multi-purpose solution is unavailable, only two sterile liquids can be used for very short-term hydration, but they offer no disinfection. The most widely accepted temporary substitute is commercially prepared, sterile saline solution. This product is a balanced salt water solution compatible with the eye’s natural environment.
Saline solution keeps lenses hydrated, preventing them from drying out and protecting the lens material’s integrity. Alternatively, preservative-free artificial tears can also be used to store lenses for a few hours. Neither sterile saline nor artificial tears contain the chemical agents necessary to kill bacteria or clean deposits. This storage method is only a temporary measure until a proper disinfecting solution is available.
Essential Function of Contact Lens Solution
Standard contact lens solution, particularly multi-purpose solution, is a complex chemical blend designed to perform three essential functions. The primary role is disinfection, which is accomplished by incorporating antimicrobial agents like polyaminopropyl biguanide or polyquaternium. These chemicals effectively kill bacteria, fungi, and other microbes that accumulate on the lens surface, significantly reducing infection risk.
The solution also contains cleaning agents, such as surfactants, which remove debris, protein deposits, and lipids that build up from tears. Without this cleaning action, deposits can cloud vision, cause discomfort, and harbor infectious agents. Finally, the solution is buffered to a specific pH and contains wetting agents to hydrate the lens material, ensuring it remains soft, comfortable, and maintains its shape. This combination of disinfection, cleaning, and hydration makes contact lens solution irreplaceable for routine care.
Post-Emergency Lens Care and Safety
If you used an emergency, non-disinfecting liquid like sterile saline for storage, the lenses must undergo a complete disinfection process before being worn again. First, discard the temporary liquid from the case and rinse the lenses with a fresh, multi-purpose disinfecting solution. Then, soak the lenses in the fresh disinfecting solution for the minimum time specified by the manufacturer (often six to eight hours).
This extended soak time ensures any contaminants introduced during temporary storage are neutralized. If the lenses were stored in anything non-sterile, such as tap water or saliva, they must be immediately discarded. After disinfection, inspect the lenses for damage or discoloration before reinsertion, and consider replacing your contact lens case, as it may have been compromised.