Your brain does, but your eyes do not become weaker or dependent because of it. A stronger prescription often feels strange for a few days up to two weeks while your brain adapts to the new image. After that, the lenses feel normal. Any later increase in your prescription comes from changes in the eye itself, not from wearing glasses.
What “Getting Used To” Glasses Really Means
When people say their eyes got used to a strong prescription, they usually mean one of two things. The first is the adjustment period, when new lenses feel odd. The second is the worry that glasses have trained the eyes to rely on them.
The first is real and temporary. The second is a myth. Separating the two clears up most of the confusion.
How Long Adjustment Takes
All About Vision reports that in most cases it takes only a few days to adjust to new prescription glasses, though for some people the adjustment can take up to two weeks. During that time you might notice mild dizziness, eye strain, or headaches.
The guide adds that a headache on the first day is not unusual, but if headaches continue after two or three days, you should call your eye doctor. You can read the details in the All About Vision adjustment guide.
Why New Lenses Can Feel Strange
Your eyes and brain both have to work harder to make sense of the new image, according to the same guide. A stronger lens changes how large objects appear and how far away they seem, so your brain has to recalibrate.
Interestingly, the adjustment is not only about strength. The guide notes that new frames can require adaptation even when the prescription has not changed. For example, swapping small rectangular frames for oversized round ones alters the curve of the lenses in front of your eyes.
Do Strong Prescriptions Make Your Eyes Dependent?
This is the fear behind the question, and the answer is no. The American Academy of Ophthalmology lists the idea as a myth and states that using your glasses will not worsen your vision or lead to any eye disease. If you need glasses for distance or reading, wearing them helps you avoid straining your eyes and gives you the best vision possible, as the American Academy of Ophthalmology explains.
Needing glasses does not mean your eyes have become lazy. It means light is not focusing properly without help.
Why Your Eyes Feel Worse Without Them
Once you have experienced sharp vision, blur becomes more noticeable. You are comparing the world to a clearer version of itself. That contrast can feel like your eyesight got worse, even though your uncorrected eyes are exactly as they were.
Can the Wrong Strength Hurt Your Eyes?
Some people worry that an overly strong prescription might harm their eyes. The Academy says wearing glasses with an incorrect prescription will not damage your eyes, but it may strain them and cause achiness or blurriness, or give you a headache, which should go away when you take the glasses off.
That is why persistent discomfort deserves a follow-up. Your eye doctor can recheck the measurements and confirm the lenses were made correctly.
Why Your Prescription Keeps Increasing
If glasses are not to blame, what drives the changes? In children, growth is a major factor. A Cochrane review of myopia in children notes that nearsightedness typically progresses faster at younger ages, according to the review on PubMed Central.
The same review found that leaving myopia undercorrected slightly increased progression in children, so skipping glasses does not protect the eyes. In adults, the focusing lens stiffens over time, which our article on presbyopia covers, and the prescription can keep shifting later in life, as discussed in why your eye prescription keeps changing after 60.
How to Adjust Faster
The best way to help your eyes adjust is simple: wear the new glasses. All About Vision advises wearing them as much as possible, because consistent wear helps your brain adapt more quickly.
Be careful with stairs, driving, and curbs for the first day or two, since distance and depth can look slightly different.
When to Call Your Eye Doctor
Contact your doctor if symptoms last beyond a week or two, or if dizziness, nausea, or headaches are severe. A frame that sits crookedly or lenses that are not centered correctly can cause the same problems as a bad prescription.
Regular checkups help too. Our guide to eye exams as you age explains how often to go.
