Blurred Vision: Definition, Causes, Symptoms, and Treatment

Published on March 17th, 2023

Updated on January 23rd, 2025

Blurred vision refers to multiple eye conditions and symptoms where the eyes are unable to focus properly, resulting in unclear and hazy vision. Blurred vision’s definition is an inability of the eyes to focus properly, resulting in blurry vision. Blurry vision causes include different eye conditions, such as refractive errors, myopia, glaucoma or macular degeneration. Blurred vision symptoms include eye floaters, hazy sight and photophobia. Blurred vision treatments include eye drops and laser surgery.

Blurred vision is caused by common eye conditions, however, some symptoms of blurred vision, such as numb arms or painful migraines, may be shared with more severe and urgent conditions and should be checked as soon as possible to identify the cause of the eyes being blurry.

What is Blurred Vision?

Blurred vision is a term for a person's vision being hazy and unclear, due to certain eye conditions, such as myopia or presbyopia. Blurred vision refers to the eyes being unable to see objects or people with full clarity, as the world appears unclear.

What does blurred vision look like?

Blurred vision looks like the world is unfocused and hazy, as up-close or distant objects lose their precise and sharp details, depending on the distance to the object. Blurred vision may also affect a person's ability to see colour, making more vibrant shades appear grey and dull.

What are the Other Terms for Blurred Vision?

Other terms for blurred vision depend on the cause of the blurred vision. Medically, it can be known as a refractive error, hyperopia, myopia, presbyopia or astigmatism. More common terms for blurred vision include hazy vision, cloudy vision and fuzzy vision.

How Common is Blurred Vision?

Blurred vision is a common eye condition that becomes more likely with age. Blurry vision caused by refractive errors such as myopia affects 20,0000 to 30,0000 Australians, according to the Centre for Eye Research Australia. Blurry vision caused by conditions such as diabetic retinopathy can be found in 1 in 3 Australians who are affected by diabetes.

What are the Causes of Blurred Vision?

The causes of blurred vision, or the blurred vision reasons, are nearsightedness or farsightedness, cataracts, glaucoma, dry eyes, astigmatism, presbyopia, age related macular degeneration (AMD), diabetic retinopathy and other retinal conditions, eye injuries and idiopathic intracranial hypertension. What causes blurred vision ranges from refractive errors, to eye diseases. The blurry or hazy vision causes are listed below.

Nearsightedness or farsightedness: Near or farsightedness causes blurred vision due to the eyes' inability to focus.
Cataracts: Cataracts cause blurred vision because the gradual clouding of the lenses causes the eye to see less clearly and interrupts focus.
Glaucoma: Glaucoma causes blurred vision because of how the condition puts pressure on the optic nerve.
Dry eyes: Dry eyes cause blurred vision because an issue with tears may fluctuate the cornea’s ability to receive light.
Astigmatism: Astigmatism causes blurred vision because the unusually shaped cornea or lens causes the eye to be unable to focus.
Presbyopia: Presbyopia is what causes blurry vision as a person gets older. Presbyopia causes blurred vision because as the lens of the eye hardens and loses flexibility it causes the quality of general vision to decrease and makes the eye unable to focus as clearly.
Age related macular degeneration (AMD): Age related macular degeneration causes blurred vision by disrupting the macula’s ability to see straight ahead and interferes with straight and forward vision, causing blurriness.
Diabetic retinopathy or other retinal conditions: Diabetic retinopathy or other retinal conditions causes blurred vision due to damaging the retina and blood vessels with high blood pressure.
Eye injuries: Eye injuries cause blurred vision by disrupting a function of part of the eye from working at full capacity, causing a general loss in vision skills.
Idiopathic intracranial hypertension (rare): Idiopathic intracranial hypertension causes blurred vision by placing pressure on the optic nerve, causing poorer vision and other eye issues.

1. Nearsightedness or Farsightedness

Nearsightedness, also known as myopia, is an eye condition where the eye struggles to focus on far distances. Farsightedness, also known as hyperopia, is an eye condition where the eyes struggle to focus on up-close objects or nearby distances. Nearsightedness or farsightedness are refractive errors caused by factors such as an unusually shaped lens or cornea. Near or farsightedness becomes a cause of blurred vision when either eye condition interferes with a person's natural 20/20 vision and causes a person to be unable to focus on certain distances without their vision being blurred.

2. Cataracts

Cataracts are an eye condition where the crystalline lens of the eye begins to become clouded instead of clear. Cataracts are usually an age related eye condition. Cataracts cause blurred vision by interfering with the lens’ ability to focus and receive light. Blurred vision occurs with cataracts because the cloudy lens causes cloudy and blurry vision that may also reduce a person's ability to perceive colour.

3. Glaucoma

Glaucoma is an eye condition where the optic nerve has been damaged, often due to rising pressure of the fluid in the eyes causing nerve damage. Glaucoma causes blurred vision by damaging the eyes’ general ability to see or deliver images to the brain. Glaucoma that causes blurred vision may be acute angle-closure glaucoma. Acute angle-closure glaucoma may pose a severe health and vision risk to any person suffering from it and seeing a doctor or eye health specialist at the first sign of its symptoms is highly recommended.

4. Dry Eyes

Dry eyes, also known as dry eye syndrome, is an eye condition where there is either an issue with the eye tear production or the tears in the eye are lacking vital substances to function properly, resulting in the eye not receiving enough lubricant or moisture, causing a gritty and sore feeling in the eye. Dry eye disease causes blurred vision because the issues with tears and tear production interfere with the cornea’s ability to focus light onto the crystalline lens, resulting in poorer and blurred vision.

5. Astigmatism

Astigmatism is an eye condition where, due to birth defects, eye development or eye injury, the crystalline lens or cornea of the eye is shaped differently than a healthy eye. Astigmatism causes blurred vision by the strange and unnatural shape of the cornea or crystalline lens improperly focusing light that the eye receives, causing vision to appear blurry and unfocused.

6. Presbyopia

Presbyopia is an eye condition where, due to ageing, the lens of the eye becomes harder and less flexible, making it unable to turn or receive light as effectively. Presbyopia causes blurred vision by the hardening lens’ becoming unable to focus as powerfully and clearly as it once could, making it harder to see in poorer lighting, possibly creating headaches and causing vision to become blurry and unfocused.

7. Age-related Macular Degeneration (AMD)

Age-related macular degeneration, also known as AMD, is an eye condition where, due to ageing, the macula of the eye becomes damaged and grows weaker, resulting in less powerful and focused front and central vision, according to the Centre for Eye Research Australia. AMD causes blurred vision by interfering with the eyes’ central vision. As the macula degenerates, the eyes’ ability to see straight ahead becomes unfocused and hazy, causing blurred vision.

8. Diabetic Retinopathy and Other Retinal Conditions

Diabetic retinopathy is an eye condition where, due to diabetes and high blood sugar levels, the retina and other blood vessels in the eye are damaged. Diabetic retinopathy causes blurry vision because the condition causes direct damage to the retina of the eye and causes continual bleeding in the eye due to new blood vessels replacing the damaged ones. This prevents the retina from functioning properly or receiving light, resulting in poorer, blurred vision. Blurred visions can also occur because of other retina related eye conditions, such as AMD or retina detachment.

9. Eye Injuries

Eye injuries refer to damage that has been inflicted directly onto the eye by blunt force or other forms of physical trauma. Eye injuries may result in damage to parts of the eye and decrease the eyes ability to function as a whole. Eye injuries cause blurry vision by possible damage to the eye interfering with an internal part of the eyes general abilities, such as damage to the cornea interfering with the ability to focus light or damage to the lens causing a lesser ability to focus, resulting in blurred or hazy vision.

10. Idiopathic Intracranial Hypertension (Rare)

Idiopathic intracranial hypertension refers to a rare condition that causes high pressure around the brain and brain, most commonly because an excess of cerebrospinal fluid is building up in the skull. Idiopathic intracranial hypertension causes blurred vision as the excess fluid in the skull puts pressure on the optic nerve.

What are the Medical Conditions that cause Blurred Vision?

The medical conditions that can potentially cause blurred vision are endophthalmitis, eye strain, conjunctivitis, migraine with aura/ocular migraine and keratitis. The following are the medical conditions that cause blurred vision.

Endophthalmitis: Endophthalmitis is a medical condition that causes the eyes to become inflamed due to possible infection of the eyes fluids, which affects focus, causes blurring, and may result in discharge from the eyes.
Eye strain: Eye strain is a medical condition where the eye feels pain and fatigue from staring or focusing on a single object or focal point for too long. The fatigue can cause the eyes to lose focus strength, resulting in blurred vision.
Conjunctivitis: Conjunctivitis is a medical condition where the conjunctiva, or eyelid, becomes inflamed and causes the eye to turn bloodshot and red. Conjunctivitis can cause blurred vision because of the infection or inflammation interfering with general vision and parts of the eye’s ability to function properly, resulting in poor focus.
Ocular migraine/Migraine with aura: Ocular migraine, also known as a migraine with aura depending on the migraine's symptoms, is a medical condition where a person may start seeing spots of colour and light across their vision, and feel a dull pain in their eyes and head. An ocular migraine causes blurred vision due to eyestrain and the colours in vision reducing focus.
Keratitis: Keratitis is a medical condition where the cornea of the eye becomes inflamed due to infection. Keratitis causes blurred vision because it affects the cornea's general ability to focus the light that it receives, resulting in poorer vision skills, poor focus and hazy vision.

What are the Symptoms of Blurred Vision?

The symptoms of blurred vision are difficulty focusing, double vision, halos around lights, eye strain or fatigue, headaches, sensitivity to light and difficulty seeing at night. The following are symptoms of blurry vision.

Difficulty focusing: Difficulty focusing is a symptom of blurred vision that is caused by eye problems such as refractive errors or lens issues.
Double vision: Double vision is a symptom of blurred vision that is caused by cataracts, or cloudy lenses, which causes a haziness in general vision.
Halos around lights: Halos around lights is a symptom of blurred vision that is caused by cataracts or possibly glaucoma, if the halo is accompanied by a painful headache.
Eye strain or fatigue: Eye strain or fatigue is a symptom of blurred vision that is caused by prolonged periods of extreme focus on a single object or item in order to overcome blurred vision.
Headaches: Headaches are a symptom of blurred vision that is caused by prolonged focus and squinting on a single object and is related to eye strain.
Sensitivity to light: Sensitivity to light, also known as photophobia, is a symptom of blurred vision that is caused by a migraine or dry eyes, making it difficult to focus on bright light due to a lack of lubrication in the eye.
Difficulty seeing at night: Difficulty seeing at night is a symptom of blurred vision that is caused by eyestrain and continued focus for an extended period of time.

What are the Blurred Vision Complications?

Blurred vision complications depend on the cause of the blurred vision and if certain symptoms of blurred vision are shared with more severe eye and health conditions that need urgent medical attention, such as a stroke or heart attack, or are a result of allergies or eye infections.

It is important to see a healthcare professional for blurred vision as soon as possible.

How is Blurry Vision Examined?

Blurry vision is examined by an optometrist performing an eye test in order to diagnose the eye conditions that may possibly be the cause of a person's blurred vision, such as refractive errors.

Where can you Seek Blurred Vision Diagnosis?

You can seek a diagnosis for blurry vision via an eye health professional such as an optometrist or an ophthalmologist, according to Health Direct, Australia’s national virtual public health information service.

What Tests are Used to Diagnose Blurred Vision?

The tests used to diagnose blurred vision are checking medical history, examining symptoms, an eye chart test, a refraction test and a slit lamp test. The following are tests used to diagnose blurred vision.

Checking medical history: Checking a patient's medical record allows a doctor or optometrist to see if the patient has had similar symptoms appear beforehand.
Examining symptoms: Examining symptoms allows a doctor or eye health professional to see exactly what eye condition or other health issue could be causing blurry vision.
Eye chart test: Eye chart tests will be used by a doctor or optometrist in order to test general visual acuity and gauge the extent of the blurry vision the patient may have.
Refraction test: Refraction tests will be used by doctors and an optometrist in order to check if the patient has the most common eye conditions and refractive errors that typically cause blurry vision.
Slit lamp test: Slit lamp tests will be used by doctors and optometrists in order to check general eye health and examine each section of the eye under greater detail.

What are the Treatments Available for Blurred Vision?

The treatments available for blurred vision are eye glasses, eye drops, medication and eye surgery. The following are treatments available for blurred vision.

Eyeglasses: Eyeglasses treat blurred vision by correcting possible refractive errors, such as myopia or hyperopia.
Eye drops: Eye drops treat blurred vision by supplying lubrication to the eyes and possibly cleaning any substances causing the blurring.
Medication: Medication treats blurred vision by preventing or addressing possible swelling or inflammation that may be causing a person's vision to become blurry.
Eye surgery: Eye surgery treats blurred vision by correcting the eye conditions and possible cause of blurred vision.

1. Eyeglasses

Eyeglasses refers to prescription lenses and frames that have a level of focus inside the lenses that helps to correct focal and refractive errors that are in a person's eyes. Eyeglasses are used to treat blurred vision by correcting possible root causes of the vision issues, such as allowing a nearsighted person to focus on further distances, reducing the blurriness of their vision.

Please be advised, any medical treatment for blurred vision should only be used with a doctor or eye health expert’s recommendation and approval.

2. Eye Drops

Eye drops are medicinal substances containing chemicals such as saline or carmellose sodium that may be applied directly to a person’s eyes in order to correct or ease conditions such as dry eyes or eye allergies. Eye drops are used to treat blurry eyes by supplying lubrication to the eye that it may not be naturally getting due to a separate eye condition.

Please be advised, any medical treatment for blurred vision should only be used with a doctor or eye health expert’s recommendation and approval.

3. Medication

Medication for blurry vision refers to medicines and chemical supplements used to treat eye and body conditions that are affecting a person's quality of life. Medication is used to treat blurry vision most specifically in the case of eye allergies and eye inflammation. Medication treats blurry eyes by reducing swelling and blocking the production of chemicals in the body that cause blurry vision symptoms, such as histamines.

Please be advised, any medical treatment for blurred vision should only be used with a doctor or eye health expert’s recommendation and approval.

4. Eye Surgery

Eye surgery refers to any type of surgical procedure performed on the eyes, such as laser eye surgery. Laser eye surgery refers to a surgical procedure where an ultraviolet laser is used to remove unwanted and excess tissue from the cornea of the eye, restoring the cornea’s total functionality, according to the Vision Eye Institute, an Australian ophthalmic provider service and research database. Laser eye surgery is used to treat blurry vision by directly addressing one of the root causes of blurry vision and correcting cataracts or other eye conditions that may be creating blurry vision in a person's sight.

Please be advised, any medical treatment for blurred vision should only be used with a doctor or eye health expert’s recommendation and approval.

Can Blurred Vision be Prevented?

Blurred vision can be prevented by regularly having eye tests to identify any possible causes of hazy vision. It is recommended to have an eye test once every two years.

How is Blurred Vision Prevented?

Blurred vision is prevented by first identifying the possible causes of a person's blurred vision and from there treating the eye condition that is preventing the eyes from focusing, or by using prescription lenses in order to correct any refractive errors that are causing blurred vision.

Is Eyesight Blurring a Result of Dehydration?

Blurred vision, headaches and fatigue are all signs of dehydration, according to FYZICAL Therapy and Balance centre, an American physical therapy franchise. This is because dehydration interferes with the body's general functions and causes blood pressure to drop, which interferes with the brain's total ability to function and can cause symptoms such as blurry vision, dizziness and weakness.

Are Nausea and Dizziness Caused by Blurred Vision?

Nausea and dizziness may be caused by blurred vision due to strain on the body and eyes creating nausea, dizziness and motion sickness.

What is the Difference Between Cloudy Vision and Blurred Vision?

The difference between cloudy vision and blurry vision is exactly what the eyes seem to be seeing. Blurry vision typically refers to the world appearing unfocused and hazy to a person's eyes, while cloudy vision refers to a misty or fog-like veneer over a person's vision when they try to see clearly. An optometrist will likely treat could vision and blurred vision very similarly.

Read Blurred Vision: Definition, Causes, Symptoms, and Treatment in other Oscar Wylee regions and their languages.