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Old Glasses Can Hurt Your Eyes. Here's When to Buy a New Pair

If you notice any of these seven signs, it's probably time for a new pair of glasses.

Laurie Garrison
3 min read
Round glasses on a light blue background.
MirageC/Getty Images

The 64% of US adults who wear prescription eyeglasses know that buying glasses is not a one-time thing. Beyond wanting new glasses for a change in style, most adults will need an updated prescription regularly. Wearing an incorrect or old prescription can cause eye strain, headaches or dizziness

So how do you know when it's time for new glasses? Here are seven signs that let you know you may need a new prescription.

Woman holding eyeglasses at the optical store.
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7 signs you need new glasses

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Do you suspect you may need a new prescription for your eyeglasses? These are the telltale signs.

You're getting frequent headaches

If you need a new eyeglasses prescription, you may be experiencing headaches. But since there are more than 150 types of headaches, it can be difficult to attribute your problems with headaches to your prescription.

If you have frequent headaches, take note of when they occur. If you commonly have a headache after watching something intensely, you may want to visit your optometrist.

You're squinting to read things

When you're scrolling on your phone or are reading, do you squint? You may do it so often you don't realize you're scrunching up your face and closing (or partially closing) one eye to get a better look at something. 

When you squint, you're changing the amount of light that enters the eye. This may make it easier to see clearly. Squinting is a clear sign it's time to update your eyeglasses prescription.

You're experiencing eye strain

Eye strain is a common condition that occurs with intense use of your eyes. This could include excessive use of your computer and other digital devices, driving long distances, reading for long periods of time and exposure to either very bright or very dim light. 

If you have eye strain, your eyes may feel tired. They may get red and watery. And your vision may become blurred. 

In addition to getting a new prescription, you may want to look at blue light blocking glasses, which can give your eyes relief if you look at a screen for hours at a time.

You have occasional blurred vision

If you have blurred vision, you just can't see things clearly. When blurred vision happens gradually, you may not even realize right away that your vision isn't as sharp and crisp as it used to be.

Concept of blurred vision - a blurred office interior.
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One of the most common reasons for blurred vision is an outdated eyeglass prescription. This can happen whether you're nearsighted (trouble seeing things far away) or farsighted (difficulty seeing things close to you) or you have astigmatism (your eye isn't shaped properly, making your vision blurry).

It's been years since you saw the optometrist

When was the last time you saw your eye doctor? If it's been more than two years, it may be time to go back and get a new eyeglasses prescription. Experts recommend adults get a full eye examination at least every two years. But if you have additional medical issues like diabetes, heart disease or cancer, you may need to see your doctor every year.

You can't read things like you used to

When you go to a restaurant, do you have to put the menu right under your nose to read it? This may be a sign you're farsighted. Or do you have to hold your phone at arm's length? This could mean you're nearsighted. Either way, not being able to read things you used to is a clear sign it's time for new glasses.

You have trouble driving at night

If you can't see the road as easily as you once did, you may be experiencing night blindness. This is when your eyes can't adjust to the lesser amount of light available at night. Often, a new prescription will solve this problem.

How often should you update your glasses prescription?

Glasses prescriptions typically expire every one to two years, so that's how frequently you can expect to update your prescription. It's best to get an eye exam when you're due, even if your prescription seems to have stayed the same. 

Regardless of how long it's been, if you notice even one of the seven signs above, it's time to book your next eye appointment. Vision is often considered the most important of our five senses, so it's important to see your eye doctor on a regular basis and get a new eyeglass prescription before your vision problems get worse.

In addition to keeping your vision sharp, when you get new glasses, you can choose new frames and give yourself a whole new look.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.