Contact lenses have a long and rich history of use. Various materials have been refined to enhance comfort, stability and quality of vision.

Patients may be prescribed either daily or extended wear soft contacts with a frequent replacement schedule. Each lens type is designed for different lifestyles and eye health.

Refractive error

Whether you wear eyeglasses or contact lenses, your vision may not be as clear as it should be. This is because of a problem called refractive error, in which the shape of your eye and cornea cause light to focus incorrectly on the retina (the light-sensitive tissue at the back of the eye).

Examples of refractive errors include nearsightedness, farsightedness, astigmatism, and presbyopia (age-related difficulty reading close objects), which are all correctionable with prescription lens technology.

Your eye doctor can test your visual acuity (the ability to see fine detail) using objective and subjective methods. Subjective testing requires you to read a chart at a distance and at close range, while objective tests such as autorefractors use machine-based measurement or handheld instruments such as a retinoscope with trial frames and trials lenses to give an estimate of your refractive error.

Irritation

The cornea is a thin surface that's easily irritated by contact lenses or by rubbing, rinsing or wiping the eyes. Also, dry eye syndrome — caused by conditions like Sjogren's and lupus — reduces the tear production that normally protects the surface of the cornea.

If irritation persists or becomes more severe, the symptoms could indicate a serious problem such as an infection, corneal ulcer, neovascularization or iritis. Contact your eye care professional immediately to have the condition identified and treated properly.

To minimize discomfort, your doctor may recommend a change in the lens material or regimen, such as switching to daily disposable lenses with a moisture-retaining surface that matches the water content and shape of your natural cornea. Some lenses use innovative technology, such as Biotrue ONEday, to keep the eyes comfortably hydrated and lubricated all day long.

Discomfort

Most contact lens wearers experience moments of discomfort from time to time. This is due to a variety of causes.

These include the wettability of the contact lens material, the design of the lens, the lens fit and the wearing modality (daily wear vs. extended wear). The eyes may also become irritated or inflamed as a result of environmental allergens such as dust, pollen and dander that stick to the surface of the contact lens and cause an allergic response.

If your eyes are red, swollen or if you have any discharge, call your eye care professional immediately. These symptoms can be a sign of a serious problem that needs to be diagnosed and treated promptly to prevent corneal scarring and permanent vision loss.

Cleaning

Taking good care of your contact lenses will reduce the risk of eye infections and other problems. Follow your manufacturer’s recommendation for cleaning and handling. For example, wash your hands before touching your contacts and dry them with a fluff-free towel. Generally, start with the same eye each time to avoid mixing your lenses up. Never use tap water or saliva (spit) to clean your contacts or case.

Rinse your lenses and clean the lens case after each use. If you wear gas permeable contact lenses, they may require a rub step with hydrogen peroxide solution in addition to this rinse step. Make sure the solution you use is preservative-free. The disinfectants in the solution kill the germs on your contact lenses and those on your eyes, eyelashes, fingers, and face.

Storage

When your lenses are stored properly, they’re a safe and effective option for correcting your vision. Contact lens wearers who follow the recommended habits can significantly lower their risk of eye infections and other complications.

Wash your hands before handling a contact lens. Tip the lens from its case into your cupped palm, and inspect it for rips and other signs of damage.

Never re-use solution or "top-off" the container with fresh liquid (unless directed by your eye doctor). The contact lens storage case should be emptied, rinsed, wiped and allowed to air dry between uses. It’s also a good idea to keep different types of contact lenses in separate cases, as they may require cleaning and disinfection methods that differ from one another.