Why Water and Contact Lenses Don’t Mix

Patients who are contact lens wearers likely have been told to avoid swimming, showering, or exposing their lenses to tap water. However, many may not understand the underlying reason for this precaution. This article will help patients understand why their eye care provider reminds them each year about this important part of their overall contact lens care.

Microorganisms present in non-sterile water sources (including hot tubs, pools, rivers, and our own faucets) have the potential to cause rare, but sight-threatening infections to the eye. Perhaps the most notorious of these organisms is Acanthamoeba. These free-living protozoans are ubiquitous, meaning they are found just about everywhere, such as in water, soil, and air. An infection by this organism is called Acanthamoeba keratitis (AK), and approximately 90% of these cases occur in individuals who wear contact lenses.¹

The material that soft contact lenses are made of is sponge-like, so it absorbs liquids it comes in contact with. Thus, one of the major risk factors for developing AK is improper contact lens care and poor hygiene practices, particularly non-sterile water exposure. Eliminating this exposure is the best strategy to prevent Acanthamoeba from contaminating contact lenses and ultimately infecting the cornea.² Proper lens care using an appropriate non-expired contact lens solution is important, and tap water should never be used. Patients should wash and dry hands before handling lenses. If lenses are not daily disposable, to clean off deposits they should be manually rubbed and rinsed with solution. To disinfect the lenses, they should be soaked in fresh solution for the recommended amount of time indicated by the manufacturer. After lenses are applied, used solution must be discarded, and the case should be rinsed with fresh solution and wiped with a clean tissue before letting it air dry on a clean surface.³ Patients should also adhere to the contact lens and case replacement schedule recommended by their eye care professional.

AK risk further increases if the cornea, which acts as a protective barrier on the surface of the eye, is unhealthy or compromised. A patient may have defects on the cornea and be asymptomatic. So, in addition to proper contact lens hygiene, routine eye examinations and contact lens evaluations are important to ensure corneal health. With these best practices, you can reduce your risk of developing AK and protect your ocular health and vision.

Contributed by: Pam Satjawatcharaphong, OD, FAAO, FSLS