Blurry vision in one or both eyes in the morning happens to a lot of people. In most cases, you have nothing to worry about, and clear vision will return after blinking or rubbing your eyes.

But a question remains, why do some people have blurry vision in the morning?

Whether you have blurry vision every morning after waking up or only sporadically, here’s a look at 10 possible reasons.

1. Dry tears

Tears lubricate, nourish, and protect your eyes, and you’re constantly producing tears even while asleep.

Sometimes, however, your nightly tears can dry on the surface of your eyes, causing blurry, hazy vision in the morning. Blinking a few times after waking up can remoisten your cornea and get rid of blurriness.

2. Eye allergies

Allergies can cause itchy, swollen, watery eyes, as well as dry eyes resulting in blurry vision after waking up.

If you experience worsening eye allergies in the mornings, the problem might be dust mites or pet dander in your bedroom. You might also be allergic to detergent used to wash your bedding.

3. Sleeping on your face

Sleeping face down can cause a condition known as floppy eyelid syndrome (FES). This is when the upper eyelid loses elasticity.

This can trigger blurry vision in the mornings, as well as tearing and eye burning. FES can happen to anyone, but it’s more common in obese men.

4. Fuchs’ corneal dystrophy

This condition causes cornea swelling while asleep, resulting in cloudy vision in the mornings. Vision gradually improves throughout the day.

Fuchs’ corneal dystrophy is more common in women than men, with symptoms typically developing around age 50.

5. Taking certain medications before bedtime

Antihistamines, sleeping aids, cold medicines, and high blood pressure medicines can reduce tear production while asleep. If taken before bed, you may experience blurry vision and dry eyes in the morning.

6. Sleeping with contact lenses

Sleeping in your contact lenses can reduce the oxygen supply to your eyes, leading to dry eyes and blurry vision after waking up. You should always take them out before falling asleep.

7. Drinking alcohol before bedtime

You might also have temporary blurriness in the mornings if you enjoyed a cocktail before bed. Alcohol causes dehydration, which can trigger dry eyes and blurriness.

8. Blood sugar problems

Blood sugar that’s too high or too low can also be the underlying cause of morning blurriness. In this case, however, you’ll have other symptoms such as dizziness and weakness.

High blood sugar can be an early warning sign ofdiabetes.

9. Oil gland problems

Sometimes, the tiny oil glands around your eyes (meibomian glands) produce too little oil and water while asleep. This can lead to eye irritation and blurry vision in the morning.

10. Sleeping underneath a fan

Sleeping with a fan might provide the perfect nighttime room temperature. However, sleeping it can dry out your skin and eyes — even when your eyelids are closed. This can trigger itchy, irritated, and blurry vision.

You don’t need to see a doctor when blurriness goes away after blinking or rubbing your eyes, or when it’s sporadic with a clear cause.

But you shouldn’t ignore unexplained, persistent blurry vision, or vision problems accompanied by other symptoms. Make an appointment with your doctor for a diagnosis.

Blurry vision in the morning could be a sign of a stroke, which is a medical emergency. If you’re having a stroke, you may have other symptoms like:

  • dizziness
  • a headache
  • tingling or numbness on one or both sides of your body
  • slurred speech

Similarly, a head injury and concussion before bed might cause blurry vision in the morning. Other symptoms of a concussion include:

  • lack of coordination
  • a headache
  • nausea
  • dizziness
  • ringing in the ear

If eye allergies cause blurry vision, your doctor might make a diagnosis after observing your symptoms (red, watery, itchy eyes). In such a scenario, allergy eye drops can improve blurriness.

Other times, however, your doctor may need to run tests to determine the underlying cause. This includes a comprehensive eye exam to measure visual acuity, as well as a test to check your optic nerve, cornea, and retina.

An eye dilation exam also helps diagnose the cause of blurry vision. Your doctor will place special eyedrops in your eyes to widen your pupil, which then allows your doctor to see the back of your eyes.

Other examinations include a test to measure tear production and the time it takes for your tears to evaporate.

Certain tests might be necessary based on your symptoms. For example, your doctor may check your blood glucose level if you have blurry eyes in the morning accompanied by fatigue, increased urination, and excessive hunger.

Blurry vision in the morning may not require treatment. Unless, of course, it’s the result of a medical condition. In this case, treatment depends on the cause.

Once you’ve treated the underlying cause, your blurry vision should improve.

For example, if cornea swelling causes blurry vision, your doctor may prescribe eyedrops to remove excess water from your cornea. In the case of eye allergies, however, taking an antihistamine can reduce allergy symptoms and stop blurriness.

Shop for antihistamines.

Applying lubricating eyedrops before going to sleep or upon waking up can remoisten your eyes. This might prevent or get rid of blurriness.

Shop for lubricating eyedrops.

Here are a few other tips to prevent blurry vision in the morning:

  • Drink plenty of fluid to keep your body hydrated (including your eyes).
  • Don’t drink alcohol before bed.
  • Dust your bedroom and wash bedding frequently.
  • Don’t sleep in your contact lenses. Clean your contact lens case daily.
  • Don’t sleep with a fan on, or pointed directly at your face.
  • Sleep on your back or side, not face down.
  • Sleep at least 7-8 hours a night. Poor sleep quality may contribute to blurry vision.

Even though blurry vision in the morning can happen to anyone, persistent blurriness might be a sign of a more serious problem.

See a doctor if your blurry vision occurs regularly, lasts throughout the day, or if you experience other symptoms along with blurriness.

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