Exposure to substances such as pollen or mold spores can cause your eyes to become red, itchy, and watery. These are symptoms of allergic conjunctivitis.

Allergic conjunctivitis is an eye inflammation resulting from an allergic reaction to substances like pollen or mold spores.

The inside of your eyelids and the covering of your eyeball have a membrane called the conjunctiva. The conjunctiva is susceptible to irritation from allergens, especially during hay fever season.

Allergic conjunctivitis is quite common. It’s your body’s reaction to substances it considers potentially harmful.

Allergic conjunctivitis comes in two main types:

Acute allergic conjunctivitis

This is a short-term condition that is more common during allergy season. Your eyelids suddenly swell, itch, and burn. You may also have a watery nose.

Chronic allergic conjunctivitis

Chronic or persistent allergic conjunctivitis can occur year-round. It is a response to allergens like dust and animal dander. Common symptoms come and go but include burning and itching of the eyes and light sensitivity.

You experience allergic conjunctivitis when your body tries to defend itself against a perceived threat. It does this in reaction to things that trigger the release of histamine.

Your body produces histamine to fight off foreign invaders.

Some substances that cause this reaction are:

  • household dust
  • pollen from trees and grass
  • mold spores
  • animal dander
  • chemical scents such as household detergents or perfume

Some people may also experience allergic conjunctivitis in reaction to certain medications or substances dropped into the eyes, such as contact lens solution or medicated eye drops.

People who have allergies are more likely to develop allergic conjunctivitis. According to the Asthma and Allergy Foundation of America, seasonal allergies affect 8 percent of adults and 7 percent of children in the United States.

If you live in a location where high pollen counts are common, you are more susceptible to allergic conjunctivitis.

Symptoms mainly affect the eyes and include:

  • red, itchy, watery eyes
  • a burning feeling in the eyes
  • a feeling of grittiness
  • sensitivity to light
  • swollen eyelids
  • puffy eyes in the morning

Your doctor will examine your eyes and review your allergy history. Redness in the white of the eye and small bumps inside your eyelids are visible signs of conjunctivitis. Your doctor may also order one of the following tests:

  • An allergy skin test exposes your skin to specific allergens and allows your doctor to examine your body’s reaction, which may include swelling and redness.
  • A blood test may show if your body is producing antibodies against specific allergens like mold or dust.
  • A doctor may take a scraping of your conjunctival tissue to examine your white blood cells. Eosinophils are white blood cells that become activated when you have allergies.

There are many treatment methods available for allergic conjunctivitis:

Home care

Here are some tips for treating allergic conjunctivitis at home:

  • Avoid rubbing your eyes, as this can make symptoms worse.
  • Rinse the eyes with artificial tears or saline eye drops, available over-the-counter from a pharmacy.
  • Apply a cool compress to relieve inflammation and discomfort.
  • Wear a hat and sunglasses for some protection from pollen.
  • Shower after coming in from outside, if pollen is a trigger.
  • Wash your hands before touching your eyes, especially after handling pets or other sources of allergens.

Medications

In more troublesome cases, home care may not be adequate. You will need to see a doctor who might recommend the following options:

  • OTC antihistamine eye drops to reduce or block histamine release
  • prescription allergy eye drops, such as bepotastine (Bepreve)
  • anti-inflammatory or anti-inflammation eye drops
  • eye drops to shrink congested blood vessels
  • steroid eye drops

Treatment can provide relief for symptoms. Symptoms should also disappear if you avoid exposure to the allergen. Recurring exposure to allergens, however, will likely trigger the same symptoms in the future.

Complications are rare with allergic conjunctivitis. In the long term, however, some people experience damage to the cornea, and this may affect their vision. The use of some medications for allergic conjunctivitis may also increase the risk of cataracts.

The best way to prevent allergic conjunctivitis is to avoid exposure to environmental triggers, but this can be hard to do.

Depending on the trigger, it may help if you:

  • use only scent-free soaps and detergents
  • install an air purifier in your home
  • vacuum and dust regularly
  • limit the carpets, soft toys, curtains, and soft furnishings in your home

What triggers allergic conjunctivitis?

Common triggers for allergic conjunctivitis include household dust, pollen, mold spores, pet dander, household detergents, and perfumes. Pollen is a common cause of seasonal allergies, but a persistent allergy may be due to dust or animal dander, allergens that are present all year.

How long does it take for allergic conjunctivitis to go away?

According to the Centers for Disease Control and Prevention (CDC), symptoms usually improve after stopping exposure to the allergen. Allergy medications and eye drops may help relieve symptoms.

What are the signs and symptoms of allergic conjunctivitis?

Your eyes will likely be red, itchy, watery, and burning, and they may be puffy in the morning.

Allergic conjunctivitis can result from exposure to allergens, such as household dust or mold. Symptoms include itching, redness, and watery eyes.

Options for treating allergic conjunctivitis include avoiding the triggers and using over-the-counter medication. If these do not help, a doctor may prescribe medication.