The iris is the colored part of the eye. It is made up of muscle fibers. The iris controls the amount of light that enters the pupil, the dark center of your eye, so you can see clearly. When the iris becomes inflamed, this is called iritis.


Iritis can be caused by an injury (traumatic iritis) or something else, such as a disease or infection (nontraumatic iritis). Often, no cause for the iritis is found.

  • Blunt trauma to the eye can cause traumatic inflammation of the iris.
  • Nontraumatic iritis is frequently associated with certain diseases, such as ankylosing spondylitis, Reiter syndrome, sarcoidosis, inflammatory bowel disease and psoriasis.
  • Infections that cause iritis may include Lyme disease, tuberculosis, toxoplasmosis, syphilis and herpes simplex and herpes zoster viruses.


Iritis usually develops quickly . It generally affects only one eye. Signs and symptoms may include any or all of the following:
  • Pain in the eye or eyebrow area
  • Eye pain that gets worse in bright light
  • Red eye, especially around the iris
  • Small or differently shaped pupil
  • Blurred vision
  • Headache


Contact your ophthalmologist (eye doctor) if you have any of the following:

  • Eye pain, including pain with bright light
  • Blurred vision
  • Redness in the eye, especially around the iris

If you cannot reach your ophthalmologist, go to the emergency room.

Questions to Ask Your Doctor

  • Are there any signs of permanent damage to the eye?
  • Are there any signs of permanent vision loss?

Exams and Tests

Iritis is diagnosed by examining the eye with a slit lamp, a special microscope used to examine the eyes. Your ophthalmologist can see cells (white blood cells) and flare (particles of protein) in the fluid inside the eye.

Two other physical examination findings help your ophthalmologist diagnose iritis:

  • Topical anesthetics do not relieve the pain associated with iritis.
  • Shining light in the unaffected eye causes pain in the affected eye if iritis is present. This is because shining light in one eye causes both pupils to constrict, or get smaller. Movement of the affected iris causes pain.
Iritis requires prescription medications and follow-up visits with an ophthalmologist, so seeking medical care is very important.
  • Use prescription medications exactly as prescribed.
  • Wear dark glasses if light makes your eye pain worse.
  • Take mild analgesics, such as acetaminophen (Tylenol) or ibuprofen (Advil), to help control some of the discomfort.

Treatment also includes eye drops to help the eye heal and decrease pain.

Your doctor will prescribe steroid eye drops unless a virus or bacteria caused the iritis. Steroid eye drops help decrease inflammation of the iris. If the eye does not get better within a week, your ophthalmologist may prescribe steroid pills or steroid injections around the eye. How long treatment lasts depends on how severe your iritis is and how much it improves with treatment.

If you have iritis, seeing your ophthalmologist for care is essential. If you have nontraumatic iritis, your ophthalmologist will evaluate you for diseases that are often associated with iritis.

Traumatic iritis usually goes away in one to two weeks. Nontraumatic iritis may take weeks, and sometimes months, to get better. Infectious iritis will get better once the infection is treated.

Some  cases of iritis, such as those that occur with sarcoidosis, ankylosing spondylitis and some other diseases, may be chronic (ongoing) or recurrent. If you have a high risk of recurrent iritis, your ophthalmologist may prescribe steroid eye drops for you to keep on hand so you can use them at the first sign of a recurrence.