Why Is My Vision Blurry?

Medically Reviewed by Shruthi N, MD on July 03, 2024
Written by Paige Fowler, Shawna Seed
9 min read

When your vision is blurry, it becomes difficult for you to see sharply or clearly. 

You may find yourself blinking, squinting, or rubbing your eyes to gain a clearer view. You might have blurry vision as a result of aging or the need for new glasses. But it can be a sign of other health problems, too.

Often, treatment for these conditions will clear up your blurred vision. Remember, though, that sudden changes to your eyesight aren't normal. If they happen, see your doctor right away.

The causes of blurred vision fall into four general categories:

Retinal. There's a problem with your retina, the structure at the back of your eye that senses light.

Clouding. The parts of your eye that light passes through to reach the retina are normally transparent. These include the cornea, lens, and jellylike substance that fills your eyeball, called the vitreous humor. If any of those things is clouded for some reason, your vision will be blurry.

Nerve issues. The path that carries messages from your eyes to your brain is disrupted in some way.

Refractive errors. These refer to problems in the way the light is focused on your retina.

Blurry vision in one eye

Blurriness that affects only one eye could signal a serious medical condition. You should talk to a doctor right away. This could be a sign of a stroke, brain tumor, detached retina, or other problem that requires immediate action.

Diabetes can damage your vision over time. It's important for your sight to manage your diabetes and have regular eye exams to catch problems early.

Diabetic retinopathy

This is an eye disease caused by diabetes. Over time, high blood sugar can damage the tiny blood vessels in your retina, the part of your eye that senses light. That can lead to swelling in a part of the retina called the macula, new and unwanted blood vessels growing in the eye, and bleeding inside the eye.

Along with blurry vision, diabetic eye disease also may cause:

  • "Floating" spots in your field of vision
  • Permanent loss of vision

Early treatment is the best way to avoid permanent damage. Learn more about the symptoms of diabetic retinopathy.

One of the key signs that you're having a stroke is a sudden, painless change in eyesight. You might have blurry or double vision. A stroke can affect the part of your brain that controls your vision.

Call 911 right away if you have either of these changes or other warning signs of stroke:

Stroke warning signs

  • Dizziness
  • Face drooping
  • Loss of balance
  • Slurred speech or other problems speaking clearly
  • Weakness or numbness in one arm
  • Severe headache
  • Disorientation

Learn more about the timeline of a stroke.

If you're pregnant, you shouldn't take blurry vision lightly. It could be a sign of preeclampsia, a dangerous condition marked by very high blood pressure and protein in your urine. Preeclampsia occurs in women who never have had high blood pressure before. It generally occurs late in pregnancy, after 20 weeks. It can have serious, life-threatening effects on you and your baby.

Preeclampsia may not cause any symptoms, but blurry vision and other sight changes such as seeing flashing lights or spots could be clues that you have it.

Get medical help right away if you suspect you have preeclampsia.

Preeclampsia symptoms

Learn more about how to lower your preeclampsia risk.

A migraine is more than a horrible headache; it's a neurological disorder. There are many other symptoms that you might have with the pain, including blurry vision and sensitivity to light. You may feel these signs even before a migraine starts, and they may last until it's over. In fact, blurry vision can be an early warning sign of migraine. It often occurs in what's called the "prodrome" phase, an early part of a migraine attack when your headache hasn't started yet.

Migraine aura

More dramatic changes to your eyesight during a migraine are called an aura. They can include:

  • Loss of part or all of your vision for a little while (usually 30 minutes or less) 
  • Seeing flashes of light
  • Seeing wavy lines or spots

To solve these problems, you'll need to work with your doctor to treat your migraines and keep them from starting. Learn more about migraine headaches with aura.

You may think of psoriasis, which is an autoimmune disorder, as something that primarily affects your skin. But psoriasis also can affect your eyes.

Psoriasis symptoms

 These are some of the common signs of psoriasis:

Uveitis

Psoriasis can cause a condition called uveitis, when inflammation leads to swelling that causes blurred vision, pain, redness, and sensitivity to light. It affects the middle part of your eye, called the uvea. The uvea includes:

  • Iris (the colored part of your eye)
  • Ciliary body, which helps the lens of your eye focus
  • Choroid, which connects the retina to other parts of your eye

This is a relatively rare condition, but it can cause serious damage to your vision.

Treatments can get rid of uveitis, but the type you need will depend on which part of your eye is affected. Learn more about uveitis.

Blurry vision is often one of the earliest symptoms of multiple sclerosis (MS).

Multiple sclerosis symptoms

Among the symptoms of multiple sclerosis are:

  • Trouble with balance
  • Bladder and bowel problems
  • Dizziness
  • Feeling very tired
  • Numbness
  • Stiffness
  • Weakness

Optic neuritis

MS can cause inflammation along the nerve that connects your eyes to your brain, called the optic nerve. That causes a condition called optic neuritis, which can cause blurry sight, loss of color vision, and pain when you move your eyes. It often happens in just one eye.

Optic neuritis doesn't necessarily mean you have MS, so talk to your doctor about what's causing it. The problem often goes away on its own, but your doctor can give you some medications to help you heal faster. Learn more about vision problems linked to MS.

A tumor in any part of your brain can make pressure build inside your skull, affecting your vision.

Brain tumor symptoms

Among the signs of a brain tumor are:

  • Drowsiness
  • Headache that won't go away
  • Nausea
  • Personality changes
  • Seizures
  • Vomiting

If your doctor thinks you might have a brain tumor, they'll use different tests to check how well your brain and spinal cord work, as well as imaging tests to see inside your head. Learn more about the different types of brain tumors.

Blurry vision is not the first sign of this nerve disease. But as Parkinson's gets worse, it can affect sight. That's because the condition may change how your eyes move. As your sight seems less sharp, you may strain your eyes because they have to work harder to focus.

Symptoms of Parkinson's disease

Other signs of this neurological condition include:

  • Poor balance and coordination
  • Stiffness in your body
  • Tremors that affect the hands, arms, legs, and face

Learn more about Parkinson's disease symptoms.

If only one eye is affected, that could be a sign of a medical issue that requires immediate action. But other, less serious conditions also can cause blurry vision in just one eye. 

Pink eye

The official name for this common condition is conjunctivitis. When you have it, the thin membrane that covers the white part of your eye and the inside of your eyelid is inflamed. That membrane is called the conjunctiva. Symptoms of pink eye include:

  • Pink or red tinge in the white part of your eye
  • Your eye itches, burns, or feels gritty
  • Swollen eyelid
  • Your eye is runny, either with tears (clear) or thicker substances that may dry into a crust

The most common cause of pink eye is a viral infection, but bacterial infections also can cause it. You might also get it as part of an allergic reaction. In babies, it can be a sign of a problem with a tear duct.

Common eye infections

Viruses, bacteria, and fungi can get into your eye, causing infection. Among the more common types of eye infection are:

  • COVID-19
  • Ocular herpes
  • Keratitis, an inflammation of your cornea
  • Endophthalmitis, which affects the inside of your eye, including the vitreous humor and aqueous humor, a thin liquid between the lens of your eye and the cornea
  • Uveitis
  • Optic neuritis

Retinal migraine

This is sometimes called ocular migraine. It's a rare condition that's part of a migraine, and it causes short bursts of blurry vision or even blindness in one eye. It can happen before your headache begins or during it. Retinal migraine is different than other vision problems caused by migraine because it affects only one eye.

Cataract

When you have a cataract, the lens of your eye -- normally clear -- becomes cloudy over time. Most people with cataracts get them in both eyes, but they can develop at different speeds. That means one eye may be affected before the other.

Eye strain

You can overwork your eyes by spending too much time looking at a screen or doing any kind of work that requires close-up vision. 

Closed-angle glaucoma

This happens when the fluid in your eye can't drain the way it should, and pressure builds up in your eye. This can damage your optic nerve and cause permanent vision loss. It's a medical emergency. Other symptoms include:

  • Headache
  • Eye pain
  • Nausea and vomiting
  • Seeing halos around light sources

Closed-angle glaucoma can affect one eye or both.

Wet macular degeneration

The macula is the center part of your retina. Your macula is important for your central vision and for seeing small details. Macular degeneration comes in two forms: wet and dry. In wet macular degeneration, this internal part of your eye starts bleeding or leaking fluid. This is a medical emergency that can cause you to lose vision in that eye suddenly. Other symptoms of macular degeneration include:

  • Dark or blind spots in your central vision
  • Trouble recognizing faces
  • Wavy vision
  • Trouble reading and driving
  • Trouble making out small details

Many conditions -- some more serious than others -- can cause blurry vision. If only one eye is affected, that can help your health-care provider narrow down the problem. Blurriness can be caused by something as simple as eye strain, or it can be related to an underlying condition such as diabetes, stroke, Parkinson's, migraine, or multiple sclerosis. Viral, bacterial, and fungal infections also can cause blurry vision. If blurry vision comes on suddenly or only in one eye, you should seek medical help right away.

Can dehydration cause blurry vision?

Yes. If your body doesn't have enough fluids, your eyes may not have enough liquid to stay lubricated. Dry eyes can cause blurry vision.

Can blurry vision go away?

This depends on the cause. Most conditions that cause blurred vision can be treated.

Does high blood pressure cause blurry vision?

Yes, high blood pressure can affect your vision. Among the eye problems it can cause are:

  • Damage to blood vessels in your retina
  • Fluid buildup under your retina (choroidopathy)
  • Damage to your optic nerve (optic neuropathy)

How to fix blurry vision naturally 

The first step is to find out what's causing your blurry vision. Your health care provider will let you know what treatment, if any, you need. Beyond that, you can take steps to promote general eye health. They include:

  • Avoid things such as dust and smoke that can irritate your eyes.
  • Use artificial tears if your eyes are dry.
  • Wear sunglasses when you're out in the sun.
  • Wear eye protection during work or hobbies that could damage your eyes.
  • Get plenty of rest.
  • Eat a healthy diet.

What is an eye stroke? 

When this happens, your optic nerve doesn't get enough blood. That can happen due to blocked vessels or insufficient pressure within them. This condition is also called anterior ischemic optic neuropathy, and it can cause sudden loss of vision.