What is a cataract?

A cataract develops when the lens in your eye, which is normally clear, becomes foggy.

For your eye to see, light passes through a clear lens. The lens is behind your iris (colored part of your eye). The lens focuses the light so that your brain and eye can work together to process information into a picture.

When a cataract clouds over the lens, your eye can’t focus light in the same way. This leads to blurry vision or other vision loss (trouble seeing). Your vision change depends on the cataract’s location and size.

Who gets cataracts?

Most people start getting cataracts around age 40. But you probably won’t notice symptoms until after age 60. Rarely, babies are born with cataracts due to a birth defect.

You’re more likely to develop cataracts if you:

  • Smoke cigarettes.
  • Live in an area with bad air pollution.
  • Use alcohol heavily.
  • Have a family history of cataracts.

How common are cataracts?

Cataracts are common among older people. More than 50% of people age 80 and older have had cataracts.

Can you get cataracts in both eyes?

You can get cataracts in both eyes. But one eye may be worse than the other or develop at a later time.

Symptoms and Causes

What causes a cataract?

The lens of your eye is mostly water and proteins. As proteins break down over time, they hang around in your eye. These lingering proteins can make your lens cloudy, so it’s hard to see clearly. This is a typical — though unpleasant — part of aging.

Some things can speed up the formation of cataracts, such as:

What are the symptoms of a cataract?

Cataracts are a common part of the eye’s aging process. Eventually, they can cause:

  • Vision that’s cloudy, blurry, foggy or filmy.
  • Sensitivity to bright sunlight, lamps or headlights.
  • Prescription changes in glasses, including sudden nearsightedness.
  • Double vision.
  • Need for brighter light to read.
  • Difficulty seeing at night (poor night vision).
  • Changes in the way you see color.

Are cataracts painful?

Cataracts don’t usually hurt. But they can cause discomfort by making your eyes more sensitive to light.

Diagnosis and Tests

How is a cataract diagnosed?

If you have cataract symptoms, see an eye doctor (ophthalmologist) for a complete exam. The doctor will need to dilate your pupil to see inside your eye. During this test, special eye drops widen your pupil (the black part of the eye). When the pupil is wide open, your doctor checks the health of your eye. Your doctor can see if you have cataracts or other problems and find out how much of your vision is blocked.

Management and Treatment

How is a cataract treated?

If your cataract symptoms are mild, you might just need a new prescription for glasses or contacts. Cataracts usually worsen over time, though. Eventually, your doctor will likely recommend surgery to remove the cataract.

At what stage should cataracts be removed?

Most people wait until a cataract causes enough vision loss to be a problem, like making it hard to read or drive. Sometimes people need cataract surgery to see and treat other eye conditions, such as age-related changes in the retina (tissue at the back of the eye) or diabetic retinopathy.

Who removes cataracts?

An ophthalmologist (doctor who specializes in eye health) performs cataract removal surgery.

How are cataracts removed?

During cataract surgery, the surgeon removes the clouded lens and replaces it with an artificial lens implant. The new lens is clear, shaped to fit your eye and personalized to your vision needs.

Cataract removal takes about an hour. It’s done with local anesthesia (medication to numb a specific area). Your doctor will use eye drops or a shot to numb your eye. You’ll be awake, but you won’t feel or see the procedure.

What are the different types of cataract surgery?

There are two types of procedures to remove cataracts:

Phacoemulsification cataract surgery

Phacoemulsification is the most common procedure for cataracts. Your ophthalmologist makes a small opening in the eye to reach the clouded lens. Using high-frequency sound waves (ultrasound) or a laser, your ophthalmologist breaks the lens into pieces. Then the doctor suctions lens fragments from your eye and puts in a new plastic lens.

Extracapsular cataract surgery

Your doctor might recommend this procedure if the phacoemulsification technique isn’t a good option for you. For example, an advanced cataract might be too dense to break apart easily.

In extracapsular cataract surgery, your ophthalmologist makes a larger opening in the eye. Instead of breaking up the lens and then removing it, your doctor removes the lens in one piece. Then the surgeon inserts the manufactured lens.

What can I expect after surgery?

After surgery, it’s typical to have a day or two of:

  • Itching.
  • Mild discomfort.
  • Watery eye.
  • Sensitivity to light.
  • Blurry vision.

For a few weeks after surgery, you may need to use eye drops. The drops help you heal, prevent infection and control the pressure inside your eye. During those weeks you’ll also want to avoid:

  • Touching your eyes.
  • Bending over.
  • Lifting heavy things.
  • Doing anything that risks injuring your eye.

How much time does it take to recover from cataract surgery?

Your eye should heal within eight weeks. But you can go about your daily activities as soon as a day after the surgery.

Is cataract surgery safe?

Cataract surgery is one of the safest and most frequently performed surgeries in the U.S. The chance of any complications is extremely low. But you should always discuss the risks of any surgery with your doctor. Some people do have an infection or vision loss after the procedure.

How painful is cataract surgery?

You shouldn’t feel anything during the cataract removal surgery. Afterward, you may have mild pain and discomfort. Your doctor can give you a pain reliever to use for the first day or two.


Can cataracts be prevented?

Developing cataracts is a typical part of aging. You can take a few steps to protect your eye health and slow the process:

  • Quit smoking.
  • Wear sunglasses and a hat with a brim to keep sun out of your eyes.
  • Get regular eye care. Have your eyes dilated once every two years after age 60. Surgery may be easier if you get treated sooner.

Outlook / Prognosis

How soon will my vision improve after surgery?

You may have some blurriness for a few days after cataract removal. But you should notice improved vision within the first several weeks. Nine out of 10 people see better after cataract removal.

You still may need to wear glasses or contacts after cataract surgery. Your prescription may change, so be prepared to buy a new pair of eyeglasses or contacts. If you’ve had laser vision repair (LASIK®), you may need to repeat it or wear glasses or contacts after cataract removal.

Will I need to have cataract surgery again in the future?

If both your eyes need cataract surgery, your doctor will probably schedule your surgeries several months apart. Separating the surgery gives both eyes a chance to heal. It also minimizes the disruption on your life. The lens implants for cataracts are permanent and usually don’t need to be replaced.

In some rare cases, you can develop what’s called a secondary cataract. Cloudiness builds up on the surface of the artificial lens weeks, months or years after surgery. It’s fixed with a quick laser surgery called posterior capsulotomy. The procedure takes just 5 minutes. Your ophthalmologist uses a laser to make an opening in the lens to let light in again. You sight should improve within 24 hours.

Living With

How can I see better without surgery?

Early on, your vision loss from cataracts may be mild. You can try managing it by:

  • Using a magnifying glass for reading.
  • Wearing polarized sunglasses, which reduce glare.
  • Using brighter light bulbs, since it’s easier to see with more light.

A note from Cleveland Clinic

As you get older, it’s typical to develop cataracts and some vision problems. But you don’t have to put up with it. Cataract removal surgery is one of the safest and most effective surgeries performed in the U.S. It’s quick and relatively painless. It gives clear eyesight back to 90% of people and rarely causes complications.

Last reviewed by a Cleveland Clinic medical professional on 04/27/2020.


  • American Academy of Ophthalmology. What Are Cataracts? Accessed 6/4/2020.
  • American Optometric Association. Cataract. Accessed 6/4/2020.
  • National Eye Institute. Cataracts. Accessed 6/4/2020.
