Potential Complications from Contact Lens Use: Causes and How It Spreads

At a glance

  • Neglecting proper eye care and contact lens maintenance can increase the risk of eye complications like keratitis.
  • Practice appropriate healthy eye habits while wearing contact lenses to prevent infections.
Man with itchy eyes


Contact lenses provide vision benefits, but they are not risk-free. Contact lens wear is linked to higher risk of keratitis or inflammation of the cornea (the clear dome that covers the colored part of the eye). Keratitis in contact lens wearers can be caused by many factors.

One type of keratitis, called microbial keratitis, can occur when germs invade the cornea. These germs—such as viruses, bacteria, fungi, or parasites (amebae)—are more likely to invade the eyes when contact lenses are worn for too long or are not cared for correctly.

Microbial keratitis is a serious type of eye infection in contact lens wearers, which can lead to blindness or the need for corneal transplant in the most severe cases.

Types of microbial keratitis

Microbial keratitis symptoms

  • Irritated, red eyes
  • Worsening pain in or around the eyes—even after contact lens removal
  • Light sensitivity
  • Sudden blurry vision
  • Unusually watery eyes or discharge

If you experience any of these symptoms, remove your contact lenses (if you wear them) and call your eye doctor immediately.

Possible complications

Other complications that are commonly linked to contact lenses usually cause milder symptoms, or no symptoms at all. They may resolve through temporarily not wearing contact lenses, or with eye drops prescribed by an eye doctor.

Some of these complications include:

  • Dry eyes
  • Allergies affecting the eyes
  • Giant Papillary Conjunctivitis: bumps that appear underneath the eyelid
  • Corneal abrasion: a scratch or scrape on the cornea
  • Contact Lens-induced Acute Red Eye (CLARE): red, irritated eyes
  • Corneal infiltrates: irritation of the cornea indicating inflammation and possible infection
  • Neovascularization: new blood vessels growing onto the cornea, sometimes causing eye redness

Prevention methods

Microbial keratitis can usually be prevented through proper eye health and care of contact lenses and supplies. Most complications can be easily treated by an eye doctor. However, more serious infections can result in vision loss or blindness if left untreated.

If you experience unusual eye irritation:

  • Promptly remove your contact lenses
  • Avoid wearing contact lenses again until advised by your eye doctor
  • See an eye doctor
Woman wearing glasses.
Always be sure to carry a pair of glasses with you—just in case you have to take out your contact lenses.