The Basics of Contact Lenses

Many people new to contact lenses have a lot of questions: What's the first step? Aren't all contacts pretty much the same? How can I tell if my contact lens is inside out? And more.

The First Step: See Your Eye Doctor

If you want to wear contact lenses, you must first see an optometrist. This is the case even if you don't normally wear glasses, and just want contacts to change your eye color. The reason? Contact lenses are medical devices that need to be prescribed, just like medicines, and properly fitted by an eyecare practitioner. In the United States, contacts can be legally purchased only with a valid written prescription.

The eye doctor will check your eyes to make sure it's okay for you to wear contacts; today, nearly everyone can, but there are a rare few who can't. Then, he or she will determine your prescription.

Once you have your Rx, you'll want go to the Good Stuff: Choosing Your Contact Lenses. The selection of contact lenses available can best be described as "vast." Don't worry about becoming overwhelmed, though: contact lenses can be broken down into several main categories based on what they're made of, how often you need to replace them, and whether you can sleep in them.

Contact lenses are made of many different types of plastic, but they are divided into two main groups: soft or GP (also called rigid gas permeable). Soft contacts contain from 25% to 79% water, are easy to adapt to and are quite comfortable. Rigid gas permeable contact lenses take longer to adapt to, but are more durable and more resistant to deposit buildup. They tend to be less expensive over the life of the lens (but the upfront cost is higher) and can offer some people crisper vision than they would have with soft contacts.

The replacement schedule of a contact lens refers to how long you can safely wear it before you need to throw it away. With GP lenses, you generally replace them every couple of years, because they are made of a very durable material (though a prescription change would necessitate new lenses). Soft contact lenses come in a wider variety of replacement schedules.