How to Compare Properties of Contact Lenses

Discuss your habits and lifestyle with your eye-care professional to choose the best contact lens. The American Academy of Ophthalmology, the American Optometric Association and the U.S. Food and Drug Administration offer comparison charts of the common types of lenses.

Rigid Gas-Permeable (RGP) Lenses

• RGP lenses must be removed from your eyes and cleaned every night but are the most durable and provide the sharpest vision. They do require a period of adjustment.

Daily-Wear Soft Lenses

• Softer materials make lenses that are more comfortable to wear and require no adjustment. Instead of cleaning the lenses at night, you throw them away and put in new lenses in the morning.

Extended-Wear Lenses

• In a wide range of materials and uses, these lenses can be worn safely for two days and the night between, or as long as seven days and six nights before they're removed for a night off. They carry minimal risk of infection because they're thrown away and replaced rather than cleaned and reused. Sometimes called "continuous-wear," another group of lenses may be worn for a full month, but the risk of infection rises steeply.

Planned-Replacement Lenses

• Crossing the categories of daily and extended wear, these lenses are cleaned between periods of wear and replaced on a schedule ranging from two weeks to six months. They can be difficult to handle and bear the same risk of infection of any lens removed, cleaned and reinserted in the eye.