Seasonal allergies and contact lenses: Wearing contact lenses when you are highly exposed to allergens, such as mold spores or pollens from grass or weeds is not a good idea. This is because allergies can result in eye irritation.
Lens material: Some contact wearers may also be allergic to the lens material itself or to protein deposits on the lenses. As the eyes need to breathe, it is best to avoid wearing lenses made of older materials or inadequately fitting contact lenses. Wearing these may not allow enough oxygen to the eye.
Over-wear: When you wear your contact lenses for too long, your eyes do not get enough oxygen. Wearing poorly fitted contact lenses also contributes to over-wear problems. Over-wearing contact lenses may possibly result in corneal abrasion or infection complications, with symptoms such as redness of the eye, blurry vision, eye pain, tears or discharge, and light sensitivity.
Corneal abrasions: Corneal abrasions, or scratches on the surface of the eye, can possibly occur because of poorly fitted contact lenses. A corneal abrasion may also occur when removing the lens or getting a fingernail in the eye. Having a corneal abrasion can be extremely painful and uncomfortable. It can even lead to an infection.
Microbial keratitis: Keratitis is an infection of the cornea that can be caused by bacteria, viruses, fungi, or protozoa or microscopic parasites. Since it is an infection, it can be serious and can pose threat to your vision.
Acanthamoeba keratitis, which is a rare but potentially blinding eye infection, is one the most common eye infection experienced by contact lens wearers. According to the Centers for Disease Control and Prevention (CDC), it accounts for 85 percent of U.S. cases. The overall incidence is approximately one to two cases per one million contact lens wearers. Poor hygiene, such as not cleaning lenses, not cleaning cases, or not using lens solution are the primary causes of infection. Those who improperly disinfect their lenses by using homemade solutions or tap water for cleaning are also more likely to get an eye infection.
Infection can also occur due to wearing contact lenses for long periods or sleeping in lenses, as well as swimming, using a hot tub, and showering while wearing lenses. Having a corneal abrasion can also increase the risk of infection. (Related: Do you sleep with your contact lenses on? Doing so increases your risk of an infection, says the CDC.)
While millions of people wear contact lenses, they are not for everyone. Contact lenses are not suitable if:
With the risks that come with wearing contact lenses, you should be committed to taking care of them properly and replacing them when necessary.