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How to know if your glasses prescription is wrong
Medically reviewed by Christine Cancar on 11th January 2022
During your eye test, the optometrist will check for any refractive errors and assess the type of vision correction you need. During the test, your optician will check your medical history, look at the overall health of the eye and record any issues. They will then create the prescription lenses needed to provide clear vision.
Sometimes, your glasses prescription can be wrong because you didn’t give accurate readings in your eye exam (especially if you’re experiencing eye fatigue). It could be due to human error from an incorrectly written prescription. It could also be because your prescription has changed over time. Just one wrong number in your prescription can dramatically change your overall vision. Any medications you are on, the quality of the measuring instruments in your eye test and your biorhythm can also all lead to fluctuations in visual performance.
What can wrong prescription glasses cause?
If your glasses prescription is even slightly wrong, it can cause several side effects such as:
This may be your eyes adjusting to new glasses, however, if blurry vision persists for more than a couple of weeks, your prescription most likely needs to be evaluated and you should contact your optician/eye care professional.
Vertigo can be caused by blurred vision and causes a dizzy sensation and being off balance when sitting or standing. It will also affect your depth perception. If you already have vertigo, wearing the wrong prescription glasses will only make it worse. You should visit your eye care practitioner if you experience your vertigo worsening. If you are having vertigo for the first time since wearing a new prescription, it is important that you not only get your prescription corrected but also visit your optician or eye care professional as it may also be the result of other serious health issues.
Even if your prescription is only slightly off, you'll still be likely to get headaches. Wearing the wrong prescription can cause your eyes to strain and as a result, you may notice frequent headaches a few days after wearing the wrong prescription. If your headaches seem to be getting worse when wearing your new glasses, then you must contact your optician again.
Other symptoms include nausea, Worse vision in one eye while the other eye is closed and eye strain.
How long does it take for your eyes to adjust to new glasses?
Sometimes you will need time to adjust to a new pair of glasses. The adjustment period can sometimes take a few days, a few weeks or even up to a month. This will depend on the individual and their type of prescription.
Is it normal for new glasses to blur?
Whilst your eyes adjust to new prescription glasses, you may find that they blur your vision or that your vision becomes distorted slightly. This is completely normal and temporary. You should find that these issues don't last long.
Can glasses actually make your vision worse?
Some people believe that wearing glasses will weaken your vision. This is because they believe that using their eyes without glasses will eventually correct their vision, but this isn’t true.
Will your eyes be ruined by wearing the wrong prescription glasses?
Although your eyes won’t be damaged by wearing the wrong prescription, it can have a negative impact on your ability to do daily tasks. You may find you have trouble driving, operating machines and concentrating for long periods of time. Imperfect vision can be irritating and distracting, even if you don’t experience some of the more uncomfortable symptoms. It’s worth going back to your optician to have your eyes checked over again.
Ensure you understand your glasses prescription
If you need glasses for the first time, it can be difficult to understand all the symbols and numbers on your glasses prescription. You should ask your optician of anything you are unsure of; you can also read our helpful guide on how to read your glasses prescription.
Quick links:How to tighten my glasses?
What is pupillary distance (PD)?
How to choose the best lenses for my prescription?