Commercial contact lens solution is specifically designed to clean the lens surface, disinfect to kill pathogens, and hydrate the lens material to maintain shape and comfort. Any alternative liquid can only serve the purpose of temporary hydration; it cannot provide the necessary disinfection to make the lens safe for re-wearing. Understand that any substitute is strictly a short-term measure to prevent the lenses from drying out before a proper solution can be acquired. Discarding the lenses entirely is always the safest option if you cannot immediately access a sterile, commercial solution.
Acceptable Temporary Storage Options
The primary goal of emergency storage is to keep the lens hydrated until a full cleaning and disinfection cycle can be performed. The safest temporary substitute is sterile, preservative-free saline intended for wound washing or nasal irrigation. This solution is balanced to match the natural salinity of the eye, preventing the lens from changing shape or causing cell damage. While sterile saline maintains lens integrity, it contains zero disinfecting agents and must never be used for long-term storage.
If sterile saline is unavailable, the next best option is to keep the lenses dry in a clean, airtight container, such as a washed shot glass or a small, unused plastic cup. Storing them dry is preferable to using non-sterile liquids, which introduce contamination. If stored dry, the lenses must be rehydrated and thoroughly cleaned before soaking in a proper multipurpose solution. If you cannot find any appropriate sterile liquid or guarantee disinfection within a few hours, the most responsible action is to dispose of the lenses.
Liquids That Must Never Be Used
Using common household liquids for contact lens storage poses a significant risk to eye health. Tap water is the most dangerous substitute because it is not sterile and contains minerals, bacteria, and microscopic organisms, notably Acanthamoeba. If introduced to the eye via a contaminated lens, this organism can cause Acanthamoeba keratitis, a devastating eye infection.
Other liquids, including bottled or distilled water, must also be avoided because they are not guaranteed to be sterile and lack the proper saline balance. Lenses stored in plain water may absorb the liquid, causing them to swell and change shape, which can lead to discomfort or corneal abrasions upon insertion. Saliva is full of oral bacteria that can transfer directly to the lens and cause severe eye infections. Homemade salt solutions are unsafe because achieving the correct sterile concentration is practically impossible, and they lack disinfecting properties.
Essential Steps Before Re-Wearing Lenses
If you have used any temporary storage method, even sterile saline, a full disinfection process must be completed before the lenses can be safely reinserted. First, obtain a fresh bottle of commercial contact lens multipurpose solution. Then, perform the “rub and rinse” technique: place the lens in your palm, add fresh solution, and gently rub the lens for the duration specified by the manufacturer, typically around 20 seconds per side.
This physical rubbing is necessary to dislodge contaminants, protein buildup, or microorganisms that settled during temporary storage. Following the rub, rinse the lens with a stream of fresh solution before placing it in a clean lens case. The lenses must then soak in the fresh multipurpose solution for the minimum recommended disinfection time, usually four to eight hours. Skipping this soaking period means the lens is not fully disinfected, greatly increasing the risk of an eye infection.
Health Risks of Improper Lens Care
The consequences of improper contact lens care or using unsafe storage liquids can be serious. Eye infections, known as microbial keratitis, develop rapidly and cause pain, redness, and blurry vision. These infections occur when bacteria, fungi, or parasites are transferred to the cornea.
One serious outcome is a corneal ulcer, an open sore on the clear front surface of the eye that often requires urgent medical intervention. Contamination from tap water can lead to Acanthamoeba keratitis, which is difficult to treat and may result in permanent visual impairment or the need for a corneal transplant. Adhering to strict hygiene and disinfection protocols is the only way to safeguard against these threats to vision.