Contact lens solutions clean, sanitize, and moisturize lenses to prevent discomfort and infection. When your primary solution is unavailable, the temptation to use a substitute is high, but the risks to your vision are severe. Understanding the specific function of proper solutions and the dangers of common household alternatives is essential for protecting your eyes until you can access a commercial product.
The Critical Distinction: Rinsing vs. Disinfecting
The most common mistake in an emergency is confusing a rinsing agent with a disinfecting one. Multipurpose or hydrogen peroxide-based solutions contain biocides that actively kill harmful microorganisms like bacteria and fungi. This disinfection process safeguards against serious eye infections.
Saline solution is a sterile, pH-balanced mixture of salt and water designed to match the natural environment of the eye. It is safe for rinsing a lens after cleaning or for moistening it before insertion. Saline lacks active antimicrobial ingredients, meaning it cannot clean or disinfect. Using a non-disinfecting solution for storage transforms the lens case into an environment where microbes can thrive.
Safe, Approved Commercial Alternatives
If your primary solution is unavailable, sterile eye products can serve limited, temporary roles. Sterile saline solution, purchased in an unopened bottle, can be used to rinse a lens or temporarily hydrate it for a few hours. This is strictly a moisturizing measure, and the lenses must be properly disinfected immediately upon obtaining a full contact lens solution.
Preservative-free rewetting drops, also called lubricating drops, are safe to use while lenses are worn to relieve dryness. These drops are formulated to be compatible with the lens material and the eye’s natural tear film. Rewetting drops are not substitutes for cleaning or storage solution and will not remove debris or kill germs.
Hydrogen peroxide-based cleaning systems are highly effective at deep disinfection. However, they require a specific neutralization step before the lenses are safe to wear. Attempting to use the unneutralized peroxide solution as a quick rinse or storage substitute is extremely dangerous and will cause a painful chemical burn to the cornea. This system is not a viable emergency alternative unless the complete kit is available and the user is trained.
High-Risk Substitutes: What NOT to Use
The danger in a solution emergency is resorting to common household liquids, which carry a high risk of causing severe eye infections. Tap water, even if potable, is not sterile and contains microorganisms toxic to the eye. The primary threat is Acanthamoeba keratitis, a rare but sight-threatening corneal infection caused by an amoeba often found in tap water.
Lenses exposed to tap water can also swell due to osmolarity differences, causing the lens to tighten on the eye and leading to corneal abrasions. Saliva is similarly dangerous, as the mouth is a non-sterile environment teeming with bacteria, including species like Pseudomonas aeruginosa. These organisms can trigger severe, rapid-onset corneal infections when transferred to the eye via a contact lens.
Homemade saline solutions, often made with water and table salt, should be strictly avoided. It is impossible to achieve the level of sterility and precise pH balance required for eye safety outside of a laboratory setting. Such mixtures introduce unknown contaminants, which increase the risk of serious infection.
Short-Term Emergency Protocol
The safest action in a contact solution emergency is to immediately remove your contact lenses and switch to wearing glasses. This eliminates the need for any substitute solution and prevents the risk of infection. If you cannot access a proper lens solution, wearing glasses is the only way to guarantee eye health.
If wearing glasses is genuinely impossible and you must store your lenses, use a fresh, unopened bottle of sterile saline solution as a last resort. The lenses should not be stored this way for longer than four hours, and they must be disinfected immediately afterward.
Any lens that has contacted a high-risk substance, such as tap water or saliva, must be immediately discarded to prevent microbial contamination. If you cannot obtain a proper disinfecting solution within 24 hours of temporary storage, it is safest to throw the lenses away, as the risk of serious eye infection increases significantly with prolonged non-sterile storage.