Key Takeaways
- Blurry vision in one eye can come from a prescription change, a slow-building eye condition, or a health issue like diabetes.
- Sudden blurriness in one eye may point to a problem with the retina or a quick rise in eye pressure.
- Flashes, a dark curtain over your sight, eye pain, or a facial droop require urgent care.
- An eye exam can help your optometrist find the cause and recommend a treatment that fits your needs.
- Regular eye exams and healthy habits can help protect your family’s vision.
Blurry vision in one eye can go unnoticed at first because your other eye compensates for it. You might only spot the difference when you cover one eye and things look softer on the other side.
Blurry vision in one eye can come from an outdated prescription, a slow-developing condition like cataracts or glaucoma, a health issue like diabetes, or a sudden problem with the retina, optic nerve, or eye pressure. A comprehensive eye exam can help your optometrist sort out which one applies to you, and some sudden changes call for emergency eye care the same day.
What Is Blurry Vision in One Eye?
Blurry vision in one eye means sight in that eye looks hazy, foggy, or out of focus. Text on your phone might look soft at the edges, and faces across the room may lose their detail.
The change can appear in seconds or build so slowly you barely notice it. Some people find their vision clears and blurs again throughout the day.
Common Causes of Blurry Vision in One Eye
Many causes of blurriness in one eye develop gradually, so you may not notice them right away.
Refractive Errors and Prescription Changes
Each of your eyes can have its own prescription. Nearsightedness, farsightedness, or astigmatism may change in one eye more than the other, so your glasses or contact lenses no longer match your visual needs.
Presbyopia often starts in your 40s and can make it difficult to read close text. You may find yourself holding a menu farther away to read it.
Eye Conditions That Develop Over Time
Cataracts form when the clear lens inside your eye turns cloudy, so the world can look like it’s behind a dusty window. Age-related macular degeneration (AMD) affects your central vision, the part you use to read a recipe or recognize a friend’s face.
The most common type of glaucoma has no symptoms in its early stages. An eye exam is often the only way to detect it before it affects your side vision.
Health and Lifestyle Factors
Diabetes can damage the blood vessels in your retina, and blurry vision can appear as that damage progresses.
Dry eyes and long hours on a screen can also leave your sight fuzzy by the end of a workday, especially if one eye dries out faster than the other.
What Causes Sudden Blurry Vision in One Eye?
A few causes of sudden blurriness can threaten your sight within hours, so don’t wait to see if it clears.
Retina and Blood Vessel Problems
A retinal tear or retinal detachment can blur your sight quickly. An eye stroke can bring sudden, often painless vision loss in one eye. A blocked retinal vein or bleeding inside the eye can also change your vision without warning.
Infection, Injury and Pressure Changes
A corneal scratch or infection can make one eye blurry, especially if you wear contact lenses. Acute angle-closure glaucoma happens when the eye’s drainage system gets blocked and pressure rises fast. It’s a medical emergency that can lead to vision loss within a day.
Inflammation of the optic nerve can blur your vision too, and it sometimes causes pain when you move your eye.
How to Tell if Blurry Vision in One Eye Is Serious
Contact your optometrist right away if blurry vision in one eye comes with any of these signs:
- Flashes of light
- A sudden increase in floaters
- A dark curtain or shadow over part of your vision
- Patches of missing vision, even if your sight comes back
Seek urgent care right away if the blurriness comes with:
- Eye pain
- Redness
- Sensitivity to light
- Nausea
- Vomiting
Facial droop, weakness in an arm or leg, or slurred speech can be signs of a stroke, so call 911.
Blurriness without pain can still be serious. Ask a friend or family member to drive you to your appointment rather than getting behind the wheel yourself.
How Your Optometrist Finds the Cause of Blurry Vision
Your optometrist starts by asking about your symptoms and overall health, including any medications you take. From there, they’ll check how clearly each eye sees and measure your eye pressure. A dilated exam lets your eye doctor look closely at your retina and optic nerve.
Treatment Options
Treatment depends on what your optometrist finds, and it may include:
- Updated glasses or contact lenses
- Eye drops or medication for an infection or inflammation
- A referral to an ophthalmologist for cataract surgery or urgent retina and pressure problems
Ways to Protect Your Eyes
Managing diabetes, blood pressure, and cholesterol supports your eye health along with the rest of your body. Regular eye exams for your whole family, from young kids to grandparents, help your optometrist track changes over time.
Good contact lens habits, like washing your hands before you touch your lenses, can help lower your risk of infection. Protective eyewear shields your eyes during yard work, home projects, or sports.
Book an Eye Exam to Find the Cause of Blurry Vision
Blurry vision in one eye has many possible causes, and an eye exam can help you find out whether you need new lenses, treatment, or a referral.
At Calgary Trail Vision Centre, our team takes the time to evaluate each eye carefully and explain what we find in plain language. Book an appointment and get clear answers about your vision.
