Contact Lenses: What to Know Before You Buy

Wonder the best type of contact lens for your vision problem, lifestyle or budget? Compare the pros and cons of specific types of contact lenses.

By Mayo Clinic staff
 Thinking about trading your glasses for contact lenses? Contact lenses are more versatile than ever before. Specialized contact lenses can even treat certain eye conditions beyond impaired vision. Whatever your reason for choosing contact lenses, proper selection and maintenance can keep you seeing clearly. Start by understanding the pros and cons of common types of contact lenses — and the ground rules for preventing eye infections.

Soft contact lenses

Soft contact lenses conform to the shape of your eye. These thin, gel-like lenses are comfortable and tend to stay in place well, so they're a good choice if you participate in sports or lead an active lifestyle. Soft contact lenses can be used to correct various vision problems, including myopia, hyperopia and astigmatism.
Soft contact lenses come in single use, daily wear and extended wear varieties.
Single use
Single use soft contact lenses are individually packaged for one-day use. You put in a new pair in the morning, then remove and discard them before you go to sleep at night.

• Pros. Single use soft contact lenses are convenient. They don't need to be cleaned and can be used intermittently.
• Cons. Single use soft contact lenses are more expensive than other types of soft contact lenses.

Daily wear
Daily wear soft contact lenses are designed to be worn daily and may be reused for a certain number of weeks, depending on the manufacturer. Typically, you insert these lenses every morning and remove them every night.

• Pros. Daily wear soft contact lenses are more economical than single use contact lenses.
• Cons. Daily wear soft contact lenses must be cleaned every day and replaced regularly to avoid protein buildup in the eye and other complications.

Extended wear
Extended wear soft contact lenses are designed to be worn continuously — both day and night — for a certain number of weeks, depending on the manufacturer.

• Pros. Extended wear contact lenses allow a certain amount of oxygen to reach your cornea even while you're sleeping, so the lenses can be worn overnight — although your eye specialist may recommend only occasional overnight use.
• Cons. Continuous use promotes the buildup of micro-organisms on the lenses and increases the risk of infection and other complications.

Hard contact lenses

Rigid gas-permeable (RGP) lenses, or hard contact lenses, are smaller and more rigid than are soft contact lenses. This makes them less comfortable than soft contact lenses, at least at first. However, gas-permeable lenses allow oxygen to pass through to the eyes, which makes them less likely to cause corneal irritation. Gas-permeable lenses also can correct certain vision problems, such as refractive errors that require high spherical or cylindrical powers, more accurately than can soft contact lenses.

• Pros. Hard contact lenses are durable and easy to care for. They also provide greater breathability than do soft contact lenses, which reduces the risk of infection. If your prescription doesn't change and you take care of your hard contact lenses, you can use the same pair for two to three years.
• Cons. Hard contact lenses are initially less comfortable than are soft contact lenses. You may need up to a week to readjust to the lenses if you stop wearing them for an extended period. Hard contact lenses are more likely to slip off the center of your eye than are soft contact lenses, which could lead to discomfort and blurred vision.

Specialized contact lenses

Sometimes specialized contact lenses are best. Common options include:

• Hybrid contact lenses. Hybrid contact lenses feature a gas-permeable center surrounded by a soft outer ring. Hybrid contact lenses may be an option if you have an irregular corneal curvature (keratoconus) or you have trouble wearing gas-permeable lenses.
• Bifocal contact lenses. Bifocal contact lenses feature two prescriptions on one lens — one to correct distance vision and the other to correct near vision. Bifocal lenses may be used to correct age-related loss of close-up vision (presbyopia). Bifocal lenses are available in daily wear soft and gas-permeable materials.
• Monovision contact lenses. With monovision contact lenses, one lens has your reading prescription and the other has a distance prescription. Monovision lenses might be helpful for presbyopia. You might also try modified monovision contact lenses, in which you wear a bifocal or multifocal lens in one eye and a single-vision lens in the other eye.

Some contact lenses are tinted, either for cosmetic or therapeutic purposes — to enhance color perception or help compensate for color blindness, for example. Avoid costume or decorative contact lenses, however. These lenses can cause pain, inflammation and potentially serious eye infections.

Getting the right fit

If you decide you want to try contact lenses, see your ophthalmologist or other eye care specialist for a thorough eye exam and fitting. Schedule follow-up exams as recommended by your eye care specialist — typically after one week, one month and six months, and then once a year.

Avoiding eye infections

Wearing contact lenses of any type increases the risk of corneal infection, simply because contact lenses reduce the amount of oxygen that reaches the corneas. Eye infections aren't inevitable, however. To prevent infections:

• Practice good hygiene. Wash, rinse and dry your hands thoroughly before handling your contacts.
• Minimize contact with water. Remove your contact lenses before swimming or using a hot tub.
• Remove your contacts before you go to sleep. This applies to extended wear contacts, too. Although extended wear contacts are designed to be worn overnight, continuous wear significantly increases the risk of eye infections.
• Take care with contact lens solutions. Use only commercially prepared, sterile products designed specifically for the type of contact lenses you wear. Carefully follow the directions given by the manufacturer. Don't use homemade saline solution, and avoid any type of contact solution that's discolored — which could be a sign that the product is out of date or contaminated.
• Follow specific tips from your eye care specialist. Don't put your lenses in your mouth to wet them, for example, and gently rub your lenses while you're cleaning them — even if you use "no rub" solution.
• Replace your contact lenses as recommended. If one or both lenses bother you before they're due for replacement, ask your eye care specialist to check them or try a new set.
• Replace your contact lens case every three to six months. Discard the solution in the contact lens case each time you disinfect the lenses. Don't "top off" old solution that's already in the case.

If your eyes are itchy or somewhat red, remove your contact lenses and use lubricating eyedrops. If your vision becomes blurry or you experience eye pain, sensitivity to light or other problems, remove your contact lenses and consult your eye care specialist for prompt treatment.