A glasses prescription provides specific instructions to correct refractive errors, common vision imperfections. An accurate prescription ensures light properly focuses on the retina, leading to clear vision and overall eye comfort. Understanding indicators of an incorrect prescription is important for maintaining optimal visual health and avoiding discomfort.
Common Signs of an Over-Corrected Prescription
Wearing glasses with a prescription that is too strong can lead to various uncomfortable symptoms. Blurred vision is a primary indicator, making objects appear fuzzy or out of focus. This can make it difficult to see fine details, read small text, or clearly discern distant objects. The eyes may struggle to focus, leading to a constant effort to compensate for the excessive correction.
This continuous effort often results in eye strain, fatigue, or discomfort. Headaches are frequent, especially around the temples or behind the eyes, as eye muscles work harder. Dizziness, vertigo, or nausea may also occur, intensifying with head movements as altered light affects spatial awareness.
Difficulty focusing on objects at different distances, particularly when transitioning between near and far vision, is common. This can feel like the eyes are constantly “pulling” or struggling to settle on a clear image. Some also report distortion or a “fishbowl” effect, where visual field edges appear curved. These symptoms arise because the visual system overworks to adapt to excessive correction.
Distinguishing Adjustment from Over-Correction
An initial adjustment period is common when receiving new glasses, especially with a significant prescription change. This period, typically a few days to two weeks, may involve mild, temporary symptoms. These include slight blurriness, minor eye fatigue, occasional headaches, brief dizziness, or subtle depth perception changes. These mild effects usually diminish as the brain and eyes adapt to the new lenses.
Symptoms of an over-corrected prescription are more severe, persistent, or worsen over time. Unlike normal adjustment, which gradually improves, over-correction symptoms often do not subside or may intensify after two weeks. Persistent blurred vision, severe headaches, or continuous dizziness and nausea beyond this timeframe suggest a prescription issue. Ignoring these prolonged or severe signs can lead to chronic discomfort and disrupted vision.
Potential Reasons for an Incorrect Prescription
Several factors can lead to an incorrect glasses prescription. Vision changes since the last eye examination are a common reason. Vision fluctuates due to aging, health conditions, or day-to-day variations. An outdated prescription may no longer meet current needs.
Measurement errors during the eye exam can also lead to an incorrect prescription. This can occur if a patient experiences eye fatigue, leading to inaccurate responses, or due to equipment calibration issues. Human error in transcribing or interpreting prescription details can also occur; even a single digit error can dramatically alter lens power.
Errors can also arise during glasses manufacturing. This includes incorrect lens power, improper astigmatism axis, or issues with pupillary distance (PD) measurement, which determines the optical center. Even with an accurate prescription, poorly fitted frames can cause lenses to sit incorrectly, leading to similar symptoms.
Steps to Take if You Suspect an Issue
If you suspect an incorrect glasses prescription, contact your optometrist or ophthalmologist. Clearly explain your symptoms, noting their severity, duration, and persistence beyond the typical adjustment period. Detailed feedback helps the eye care professional understand the problem.
Schedule a follow-up appointment for re-evaluation. During this visit, the optometrist will re-test your vision and verify your current lenses match prescribed values. They may also check frame fit and optical center alignment. Avoid trying to “get used to” severe or worsening symptoms; prolonged discomfort indicates professional intervention is needed. Your eye care provider can then adjust your prescription or glasses for comfortable, clear vision.