Buying Lenses and Getting Fitted: Two Different Things

In the United States, contact lenses are a prescription item, just like medicines. Even if you already have an eyeglass prescription, you will need a contact lens prescription that contains additional information. By law, you have the right to obtain your contact lens prescription, but a contact lens fitting is required to correctly prescribe contacts. It cannot be written from a glasses prescription.

Years ago, replacement contact lenses were available only from eye doctors. Now, the lenses themselves can be purchased from a variety of vendors, but the need for eye exams and contact lens fittings by the eye doctor is as important as ever.

A contact lens is a medical device. If it's not properly prescribed, you may not see well. More importantly, a poorly fitting lens — or one made from a material not well-suited to your eyes — could result in discomfort, inflammation, swelling, abrasion, or another problem that could, in rare cases, result in permanent eye damage or vision loss.

That, and the risk of infection, are also why it's unwise to share contact lenses with other wearers.