Allergic Conjunctivitis

What is allergic conjunctivitis?

Allergic conjunctivitis is a type of pink eye that occurs when allergy-causing foreign substances (allergens) cause inflammation in your conjunctiva. The conjunctiva is a thin membrane that lines your eyelids and helps protect the whites of your eyes (sclera) and keep them moist.

In many people, the foreign substances are harmless. But if you have allergies, your immune system views them as harmful “invaders,” like bacteria or viruses. It then reacts to remove them from your body, causing allergic conjunctivitis symptoms.

Allergic conjunctivitis usually affects both eyes.

What are the types of allergic conjunctivitis?

The two most common types of allergic conjunctivitis include:

• Seasonal allergic conjunctivitis (hay fever conjunctivitis). Seasonal allergic conjunctivitis typically occurs during the spring, summer and fall, when trees, grasses and weeds produce lots of pollen. Another name for seasonal allergic conjunctivitis is acute allergic conjunctivitis. “Acute” means it develops suddenly. This is the most common type of allergy.
• Perennial allergic conjunctivitis (year-round allergic conjunctivitis). Perennial allergic conjunctivitis may occur throughout the year. Common causes include pet dander and dust mites. Another name for perennial allergic conjunctivitis is chronic allergic conjunctivitis. “Chronic” means it continues or reoccurs often over a long time.

How common is allergic conjunctivitis?

Allergic conjunctivitis is common. It may affect up to 40% of people at some point in their lives.

What are the symptoms of allergic conjunctivitis?

Allergic conjunctivitis symptoms commonly include:

• Itchy or burning eyes.
• Puffy or swollen eyes.
• Watery eyes.
• Red eyes.
• Stringy or watery, yellow-white eye discharge.
• Allergic shiners.

Some people may also have an itchy or runny nose and sneezing.

What causes allergic conjunctivitis?

Common allergic conjunctivitis causes include:

• Pollen.
• Dust mites.
• Mold spores.
• Pet dander.
• Chemicals or fragrances in soaps, detergents, deodorants, moisturizers and cologne/perfume.

Is allergic conjunctivitis contagious?

No, unlike bacterial or viral conjunctivitis, allergic conjunctivitis isn’t contagious.

Who does allergic conjunctivitis affect?

Anyone can get allergic conjunctivitis. But you’re more likely to have or develop it if you have allergies or a biological family history of allergies. You may also be at greater risk of allergic conjunctivitis if you have pets or live in an area with high pollen counts.

How is allergic conjunctivitis diagnosed?

A healthcare provider will review your health history and ask about your symptoms. Tell them if you have any allergies or if anything irritating has gotten in your eyes recently. They’ll look at your eyes for symptoms of conjunctivitis, including:

• Redness.
• Bumps on the inside of your eyelids (giant papillary conjunctivitis).

If they suspect you have allergic conjunctivitis, they may refer you to an allergist (immunologist). An allergist may order allergy tests to confirm their diagnosis, including:

• Skin prick (scratch) test. During this test, the allergist uses a thin needle to gently scratch your skin and introduce possible allergens. They’ll then measure any reactions on your skin.
• Blood test. The allergist will take a small blood sample from your arm and send it to a lab. The lab will add possible allergens and check if antibodies develop.

How do I know if my conjunctivitis is allergic or bacterial?

It can be difficult to tell what causes conjunctivitis. But itchy, watery eyes are generally more common with allergic conjunctivitis and are present in both eyes. Viral or bacterial conjunctivitis typically only involves one eye. Allergic conjunctivitis also lasts longer than bacterial or viral conjunctivitis. Your symptoms may go away and come back throughout the allergy seasons.

If you have conjunctivitis symptoms, it’s best not to guess. Contact a healthcare provider to get treatment.

How do you treat allergic conjunctivitis?

The only way to treat allergic conjunctivitis is to avoid the cause. First-line treatment typically involves avoiding touching your eyes, home remedies and over-the-counter (OTC) or prescription medications to help ease your symptoms.

Home remedies may include:

• Regularly flushing your eyes with water.
• Applying a cold compress to your eyes.

Over-the-counter or prescription medications may include:

• Artificial tears.
• Ketotifen eye solution.
• Bepotastine eye drops.
• Azelastine eye solution.
• Cetirizine eye solution.
• Antihistamines, including fexofenadine, loratadine or cetirizine.

In severe cases of allergic conjunctivitis that you can’t manage with home remedies or over-the-counter or prescription medications, a healthcare provider may recommend allergy immunotherapy (allergy shots or allergy drops). They’ll expose you to small amounts of allergens and gradually increase the dosage over several months. Gradual exposure creates a tolerance to the allergen. The next time you encounter the allergen, you won’t have symptoms, or they’ll be mild.

Can Benadryl help allergic conjunctivitis?

Yes, Benadryl® (diphenhydramine) can help treat allergic conjunctivitis symptoms. However, one of its side effects is sleepiness. It’s a good idea to take it before going to sleep.

Allergists recommend taking second-generation antihistamines rather than diphenhydramine. Second-generation antihistamines are more effective, have fewer side effects and have no association with dementia.

How soon after treatment will I feel better?

In general:

• Antihistamines start to work about 30 minutes after you take them.
• Allergy eyedrops start to work after about an hour.
• Allergy immunotherapy may start to work within several weeks. But it may take up to six months or longer to notice your symptoms decrease.

Can allergic conjunctivitis be prevented?

Avoiding known allergens is the best way to prevent allergic conjunctivitis. You may also take antihistamines or other medications daily to help manage your symptoms.

Other tips to help avoid allergic conjunctivitis symptoms include:

• Frequently washing your hands.
• Regularly vacuuming rugs, carpets and other surfaces to help remove dust and pollen.
• Using a high-efficiency particulate (HEPA) air filter to remove airborne allergens from your home.
• Keeping your windows closed and using air conditioning during allergy seasons to reduce the amount of pollen entering your home.
• Don’t smoke or vape indoors.

What can I expect if I have allergic conjunctivitis?

You can cure allergic conjunctivitis with allergy shots. You can also help reduce the symptoms by avoiding known allergens and taking medications.

How long can allergic conjunctivitis last?

It depends. Your body is unique, including your immune system. Your allergic conjunctivitis symptoms may last less than an hour. They can also last for days, weeks or even months. It depends on what you’re allergic to and the severity of your allergy.

When should I see a healthcare provider?

See a healthcare provider, allergist or eye care specialist if you regularly have allergic conjunctivitis symptoms that affect your day-to-day quality of life.

What questions should I ask a healthcare provider?

You may want to ask your provider:

• How will you diagnose allergic conjunctivitis?
• What specific allergens are causing allergic conjunctivitis?
• What medications do you recommend?
• What’s the complete list of side effects for your recommended allergic conjunctivitis medications?
• Should I take medications every day or only when I develop symptoms?
• How do I know when I have allergic conjunctivitis or bacterial or viral conjunctivitis?

What can be mistaken for allergic conjunctivitis?

People often mistake bacterial or viral conjunctivitis with allergic conjunctivitis. A healthcare provider can usually diagnose the different types of pink eye according to:

• Your symptoms.
• Your age.
• How much discharge you have.
• If you also have an ear infection.
• The color of the whites of your eyes.
• Whether it affects one or both of your eyes.

A note from Cleveland Clinic

Allergic conjunctivitis can make you dread the spring and summer months or keep you away from friends or family who have pets. But you can still enjoy the longer days, warmer temperatures and pet scratches by taking a few extra steps. You can help avoid allergens by running a HEPA filter, vacuuming regularly and keeping eyedrops on hand. Talk to a healthcare provider about what medications can help reduce or prevent allergic conjunctivitis symptoms.