After a visit to the eye doctor, you will get a prescription if you need corrective lenses. The prescription will only be valid for a fixed time; eyeglass prescription expiration periods vary but are usually one to two years.
The expiration date is the last day that your prescription can legally be used by optical shops and labs to make glasses or provide contact lenses. With contacts, doctors will only provide enough lenses to get you through that date.
The date is not an indication of when the lenses physically expire. Contact lens expiration dates are printed on the packaging and are unrelated to the prescription expiration, and eyeglass lenses can last indefinitely, as long as the lens is carefully protected.
Rather, the expiration on your prescription indicates that your eyes may have changed in that time. Generally, eye doctors recommend getting your eyes checked once a year if you have corrective lenses. Of course, eyes can change in a shorter period, but for most patients once a year is often enough.
What Happens if My Prescription Changes?
Using an out of date eyeglass prescription can leave you wearing glasses that do not correct your vision well. If the refractive errors (like astigmatism, myopia, or hyperopia) of your eyes have changed, your vision will be blurry even with glasses or contacts. Fortunately, wearing glasses of the wrong prescription will not damage your eyes, according to the Mayo Clinic, despite prevailing myths to the contrary.
Other Benefits of Getting Regular Eye Exams
Getting regular eye exams ensures that your prescription is correct for clear vision, but it also helps detect other problems early. Diseases like diabetes, lupus and other autoimmune diseases, and certain types of cancer can all be identified in some patients through an eye exam, so getting regular exams increases your chances of catching them early, which in turn improves treatment outcomes for many diseases
The eyeglass prescription expiration is best used as a reminder to get regular eye exams. Your new prescription may simply confirm that your expired prescription is still correct and that you can continue to use your old glasses and contact lenses. Otherwise, use your new prescription to ensure optimal visual acuity.
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