Some people who wear contact lenses do not know that contact lenses and water are a bad combination—even when being worn. This includes wearing them while showering, swimming, or using a hot tub.
Water can introduce germs to the eyes through contact lenses
Anyone who has swam underwater or even showered while wearing contacts will tell you that it’s definitely not comfortable on the eyes. This is because water can cause soft contact lenses to change shape, swell, and stick to the eye. Even removing the contact lenses afterwards can be a painful ordeal. This can scratch the cornea (the clear dome that covers the colored part of the eye), which makes it easier for germs to enter the eye and cause infection.
Most water is not germ-free. There are many different kinds of germs in water that can cause eye infections, but a particularly dangerous germ—an ameba called Acanthamoeba—is commonly found in tap water, lake water, well water, and other water sources. This germ can cause a very severe type of eye infection called Acanthamoeba keratitis, which is often very painful and difficult to treat—sometimes requiring a year or more of treatment. Although rare, this type of infection can result in the need for a corneal transplant, or blindness.
Keep contact lenses away from all water
For contact lens wearers, it is best to remove lenses before showering, swimming, or using a hot tub—and contact lenses should never be rinsed or stored in water. It is also important to wash and dry hands well before handling lenses, and to clean contact lens cases with solution rather than water to avoid contaminating the lenses with germs found in water.
For those who are actively involved in swimming or other water sports and concerned about being able to see well enough without wearing lenses, prescription goggles may be a good option—or possibly even a different form of vision correction, such as laser eye surgery.
Throw away or disinfect contact lenses that touch water
If water touches contact lenses for any reason, take them out as soon as possible. Throw them away, or clean and disinfect them overnight before wearing them again. This may help to reduce the risk of infection, but these recommendations are not based on scientific testing. The safest option is to keep contact lenses away from all water.