There are a number of causes of blurry vision in one eye. Among the most common ones are refractive errors, which can lead to long- or short-sightedness. Other possible causes include infections, migraine, and cataracts.
Most causes of blurry vision are not serious. However, it is important to consult a doctor about sudden or persistent blurry vision, as it could be a symptom of a condition that requires treatment.
This article will look at some of the causes of blurry vision in one eye, along with the symptoms and treatments.
In many cases, blurry vision is not a sign of a life threatening condition. However, sudden vision changes can sometimes mean a person needs emergency treatment. Being aware of the signs of these conditions can help with deciding when to seek help.
Anyone who experiences blurry vision along with any of the following symptoms should seek emergency medical attention:
- a sudden, severe headache
- a headache following a knock to the head
- difficulty staying awake
- loss of consciousness
- drooping or numbness on one side of the face
- inability to raise one or both arms
- slurred speech
- sudden vision changes, such as flashes of light
- many more eye floaters than usual
- vision that resembles a curtain being pulled over the eyes
Read on to find out about some of the more common causes of blurry vision in one eye.
Refractive errors include:
- nearsightedness, or myopia
- farsightedness, or hyperopia
- astigmatism, or distorted vision at all distances
- presbyopia, or difficulty seeing objects up close
The most common symptom of a refractive error is blurry vision, but it can also cause:
Eyeglasses or contact lenses can help people with refractive errors see more clearly. However, some people may need surgery.
Bacteria, fungi, and viruses can all cause an eye infection, and they can affect one or both eyes. Potential symptoms of an eye infection include:
- red or bloodshot eyes
- discharge or crust around the eyes
- vision problems, including blurry vision
If a person has the symptoms of an eye infection, they should seek medical care. Depending on the cause, treatment could involve eye drops, topical medications, or oral antibiotics.
Aura symptoms can include:
- blurry vision
- short-term vision loss
- seeing shapes or zig-zag lines
- difficulty speaking
According to the American Migraine Foundation, these symptoms will usually last 20–60 minutes for those who experience aura. People can also have silent migraine, which is a migraine with aura but no pain.
Treatment for migraine usually involves pain relievers. Over-the-counter medications may be sufficient for those with an occasional migraine. However, those with frequent episodes may require prescription options, such as triptans, to manage the condition.
The symptoms of cataracts can come on over time. They include:
- blurry vision
- hazy vision
- less colorful vision
- difficulty seeing at night
- difficulty reading
- seeing double
- seeing a halo around lights
The only way to treat cataracts is through surgery. During the operation, a surgeon will replace the clouded lens with an artificial one.
Age-related macular degeneration (AMD) affects the macula, which is the part of the eye that enables people to see fine details. The condition can start in one eye and progress to the other, causing a loss of sharp or central vision.
There are two types of AMD:
Wet AMD occurs when blood vessels form behind the retina and under the macula. These bleed and leak into the eye, scarring and damaging it.
Straight lines appearing wavy is an early symptom of wet AMD.
As people get older, the macula gets thinner, leading to blurry vision. This is the most common form of AMD, accounting for
There is no cure for either type of AMD. However, there are things people can do to slow its progression, including:
- stopping smoking
- eating a balanced diet
- exercising regularly
- maintaining healthy blood pressure and cholesterol levels
In people with wet AMD, doctors may also recommend anti-vascular endothelial growth factor drugs or laser treatment.
There are often no early symptoms of diabetic eye disease, but a person may experience:
- blurry vision
- vision that changes from day to day
- areas of darkness or vision loss
- a loss of color vision
- dark strings or floaters
- flashes of light
It is important for people with diabetes to get annual dilated eye exams, as these can help doctors detect early signs of damage.
People can lower the risk of these complications by managing their blood glucose levels, blood pressure, and cholesterol levels.
Treatment for existing diabetic eye disease may involve medications, laser procedures, surgery, or a combination of all three.
Sometimes, blurry vision is a sign of stroke. A stroke happens when something stops blood from getting to part of the brain. This might be a blood vessel blockage or rupture.
People can remember the symptoms of a stroke by acting
- face drooping
- arm weakness
- speech difficulty
- time to call 911
Sudden trouble seeing or walking or a severe headache can also be symptoms of stroke. Treatment may include medications to break up blood clots, procedures to repair blood vessels, or surgery.
If a person has these symptoms, do not hesitate to call for an ambulance. Paramedics can begin treatment on the way to the hospital.
Some people with COVID-19 experience conjunctivitis, which can cause blurry vision, red or watery eyes, and a sensation that a foreign object is in the eye. As with other types of viral conjunctivitis, these symptoms will usually go away on their own.
However, it is important to stay indoors and seek testing if COVID-19 is a possibility. Even with few or mild symptoms, it is possible to transmit the virus that causes COVID-19 to others.
Other symptoms of COVID-19
- fever or chills
- shortness of breath or difficulty breathing
- muscle or body aches
- loss of taste or smell
- sore throat
- stuffy or runny nose
- feeling or being sick
Anyone who suspects they have COVID-19 can find out how to get tested by contacting their local health authority or visiting its website.
A number of things can cause blurry vision in one eye. Refractive errors are a common cause, as are age-related conditions, such as cataracts and AMD. Some people with migraine may experience blurry vision if they get aura or silent migraine.
A doctor can diagnose the cause of blurry vision and recommend the best options for treatment. However, if a person may have conjunctivitis as a result of COVID-19, it is important to call ahead before visiting a healthcare professional in person.
People with sudden vision changes or loss should seek immediate medical help, particularly if they also have underlying conditions, such as diabetes.