Your Guide to Night Blindness

Medically Reviewed By Ann Marie Griff, O.D.
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Night blindness, or nyctalopia, reduces your ability to see at night or in low-light conditions. It is typically a symptom of an underlying condition. Night blindness does not affect your vision during the daytime. With night blindness, you will experience reduced vision when in the dark. However, it does not mean that you are completely unable to see anything at night.

Night blindness can make it hard to move around in the dark, and you may also find it difficult to drive at night. If this is the case, your eye doctor will be able to identify any underlying conditions.

Read on to learn more about night blindness, including information about diagnosis and treatments.

What is night blindness?

A bridge appears blurry.
Javier Pardina/Stocksy United

Night blindness, also known as nyctalopia, is when the eye finds it difficult to see in dark or dimly lit areas. It occurs when the rods in your eye do not work properly.

What happens to the eyes in low light?

When your eye focuses at night, the pupil becomes wider to allow more light. This light travels to the retina at the back of your eye, which contains the cones and the rods.

Cones are responsible for color vision, allowing us to see in the daytime and in well-lit areas. Rods provide black-and-white vision, which allows us to see in the dark. If the rods do not work properly, they cannot receive information properly from the pupil, reducing your ability to see at night.

Vs. congenital stationary night blindness

Congenital stationary night blindness (CSNB) refers to a nonprogressive retinal disorder or night blindness that occurs from birth. CSNB is usually a result of a rare genetic disease.

What causes night blindness?

As night blindness is usually a symptom of an underlying condition affecting the eye, it can occur due to several causes.

Possible causes of night blindness include:

  • Cataracts: The focusing lens of the eye becomes clouded, causing vision to become blurry. Cataracts affect over 20 million people worldwide.
  • Glaucoma: A progressive eye disease, glaucoma causes vision loss due to nerve damage. It is the biggest cause of irreversible blindness. Learn more about glaucoma.
  • Myopia: Shortsightedness, or myopia, can cause night blindness. Myopia with astigmatism can also make it difficult to see at night.
  • Vitamin A deficiency: If you have a vitamin A deficiency, it may be more difficult to see in darker environments.
  • Diabetic retinopathy: If you have diabetes, you may experience diabetic retinopathy. It affects around 1 in 3 people with diabetes and causes progressive damage to the retina.
  • Retinitis pigmentosa: Retinitis pigmentosa refers to a group of diseases that cause cells in the retina to break down over time. It is a genetic disorder.

How do you know if you have night blindness?

Symptoms of night blindness can vary depending on the underlying cause of the condition. However, common symptoms can include:

  • cloudy or blurry vision in low-light environments
  • seeing halos or glare around lights
  • sensitivity to light
  • excessive squinting at night
  • trouble adjusting from brightly lit areas to dimly lit areas
  • difficulty with seeing objects in the distance in low-light environments
  • difficulty seeing objects or faces in low-light environments
  • complete loss of vision for more than a few minutes when entering a dark room

If you experience any of these symptoms, contact your eye doctor to arrange an eye test. They will be able to identify any underlying causes.

View our Eye Health hub for more information about symptoms of eye conditions.

How is night blindness treated?

Treatments for night blindness will depend on the cause of the condition. Possible treatments for night blindness can include:

  • medicated eye drops to reduce the effects of glaucoma
  • corrective lenses for shortsightedness or astigmatism
  • vitamin A supplements if the symptom occurs due to a vitamin A deficiency
  • anti-VEGF medication for treating diabetic retinopathy
  • laser treatment or surgery for glaucoma or diabetic retinopathy

Night blindness may occur due to a genetic or congenital condition such as Usher syndrome, retinitis pigmentosa, or congenital stationary night blindness. It is not possible to treat night blindness in these conditions. However, your doctor will be able to advise on how best to manage your condition.

Your eye doctor will be able to advise on the best course of treatment for you. Following the treatment plan is the best way to reduce night blindness.

When should I contact a doctor?

It is important to contact your eye doctor as soon as you notice any changes in your vision. Even if you are not due for a routine eye appointment, scheduling an eye test can help to prevent any underlying conditions from worsening.

How is night blindness diagnosed?

To diagnose night blindness, your eye doctor will ask questions about your symptoms and your eye health history. They will also conduct a thorough exam to rule out any other eye conditions.

A night blindness test can include the Pelli-Robson contrast sensitivity chart. This chart contains rows of letters, starting with black or dark gray letters, with each row being a lighter shade against a white background. Your eye doctor will ask you to read out these letters.

In some cases, your doctor will conduct a blood test to see if you have a vitamin A deficiency. Vitamin A deficiency can lead to night blindness.

What are the risk factors for night blindness?

As eyesight tends to worsen as we get older, night blindness is more likely to occur later in life. Aside from age, various risk factors may make you more likely to have a weaker vision at night.

Risk factors of night blindness include:

  • astigmatism or being shortsighted
  • having a history of eye conditions such as cataracts or glaucoma
  • having a family history of night blindness
  • diabetes, which can lead to diabetic retinopathy
  • taking glaucoma medication that narrows the pupils
  • having a deficiency in vitamin A or having a disorder that reduces your ability to absorb vitamin A

Is it possible to prevent night blindness?

It can be difficult to prevent night blindness as it typically occurs due to underlying eye conditions. However, there are steps that you can take to reduce the risk of developing night blindness.

Night blindness prevention steps include:

  • attending regular eye appointments for early detection of any eye conditions
  • eating a diet rich in vitamin A, or taking vitamin A supplements to prevent deficiency
  • wearing sunglasses to reduce exposure to UV rays, which can worsen cataracts and macular degeneration
  • exercising regularly to reduce eye pressure and lower blood sugar

FAQs

Can night blindness be fixed?

It is possible to treat many causes of night blindness, which can fix night blindness. Treatments can include eye drops, corrective lenses, and surgery, depending on the condition. If night blindness is due to congenital conditions, it may not be possible to fix it.

Do I need glasses if I can’t see at night?

Your doctor may prescribe corrective lenses if you cannot see well at night. These lenses may be different from any glasses or contact lenses that you wear during the day, as night blindness results from problems with the rods of the eyes. Rods are responsible for helping us see at night.

Can humans develop night vision?

A human cannot see in complete darkness. However, you can see at night if there is some source of light present, such as starlight or moonlight. It is only possible to see things in black-and-white in dark environments.

Does night vision get worse with age?

As you age, your vision will naturally worsen. Therefore, you may develop eye conditions that cause or worsen your ability to see at night. Attending regular eye appointments can help your eye doctor detect early signs of eye disorders.

Learn more

Summary

Night blindness means that your eye struggles to see at night or in low-light environments. This condition is due to damage to the rods in your retina, which are responsible for helping you to see things in black-and-white at night.

Night blindness is typically a symptom of an underlying condition, such as cataracts, glaucoma, or diabetic retinopathy. It is possible to treat most causes of night blindness. Treatment options include eye drops, lenses, and surgery.

Your eye doctor will be able to carry out a thorough eye exam, usually involving reading out letters in different shades of gray. Once they have identified the cause of night blindness, they will be able to advise on the best treatment plan for you.

Contact your eye doctor if you experience symptoms of night blindness or if you notice any changes in your vision.

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Medical Reviewer: Ann Marie Griff, O.D.
Last Review Date: 2022 Apr 20
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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