Allergic conjunctivitis
Conjunctivitis - allergic seasonal/perennial; Atopic keratoconjunctivitis; Pink eye - allergic
The conjunctiva is a clear layer of tissue lining the eyelids and covering the white of the eye. Allergic conjunctivitis occurs when the conjunctiva becomes swollen or inflamed due to a reaction to pollen, dander, mold, or other allergy-causing substances.
Causes
When your eyes are exposed to allergy-causing substances, a substance called histamine is released by your body. The blood vessels in the conjunctiva become swollen. The eyes can become red, itchy , and teary very quickly.
Conjunctiva
The conjunctiva is a thin membrane that covers the inner surface of the eyelid and the white part of the eyeball (the sclera). Inflammation of the co...
Itchy
Itching is a tingling or irritation of the skin that makes you want to scratch the area. Itching may occur all over the body or only in one location...
Teary
Watery eyes means you have too many tears draining from the eyes. Tears help keep the surface of the eye moist. They wash away particles and foreig...
The pollens that cause symptoms vary from person to person and from area to area. Tiny, hard-to-see pollens that may cause allergic symptoms include grasses, ragweed and trees. These same pollens may also cause hay fever.
Your symptoms may be worse when there is more pollen in the air. Higher levels of pollen are more likely on hot, dry, windy days. On cool, damp, rainy days most pollen is washed to the ground.
Mold, animal dander, or dust may cause this problem also.
Allergies tend to run in families. It is hard to know exactly how many people have allergies. Many conditions are often lumped under the term "allergy" even when they might not truly be an allergy.
Allergies
An allergy is an immune response or reaction to substances that are usually not harmful.
Symptoms
Symptoms may be seasonal and can include:
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Intense itching or
burning eyes
Burning eyes
Eye burning with discharge is burning, itching, or drainage from the eye of any substance other than tears.
- Puffy eyelids, most often in the morning
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Red eyes
Red eyes
Eye redness is most often due to swollen or dilated blood vessels. This makes the surface of the eye look red or bloodshot.
- Stringy eye discharge
- Tearing (watery eyes)
- Widened blood vessels in the clear tissue covering the white of the eye
Exams and Tests
Your health care provider may look for the following:
- Certain white blood cells, called eosinophils
- Small, raised bumps on the inside of the eyelids (papillary conjunctivitis)
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Positive skin test for suspected allergens on
allergy tests
Allergy tests
Allergy skin tests are used to find out which substances cause a person to have an allergic reaction.
Allergy testing may reveal the pollen or other substances that trigger your symptoms.
- Skin testing is the most common method of allergy testing.
- Skin testing is more likely to be done if symptoms do not respond to treatment.
Treatment
The best treatment is to avoid what causes your allergy symptoms as much as possible. Common triggers to avoid include dust, mold and pollen.
Avoid what causes your allergy symptoms
Hay fever - self-care; Seasonal rhinitis - self-care; Allergies - allergic rhinitis - self-care
Some things you can do to ease symptoms are:
- Use lubricating eye drops.
- Apply cool compresses to the eyes.
- DO NOT smoke and avoid secondhand smoke.
- Take over-the-counter oral antihistamines. These medicines can offer more relief, but they can sometimes make your eyes dry.
If home-care does not help, you may need to see a provider for treatments such as eye drops that contain antihistamines or eye drops that reduce swelling.
Mild eye steroid drops can be prescribed for more severe reactions. You may also use eye drops that prevent a type of white blood cell called mast cells from causing swelling. These drops are given along with antihistamines. These medicines work best if you take them before you come in contact with the allergen.
Outlook (Prognosis)
Symptoms often go away with treatment. However, they can persist if you continue to be exposed to the allergen.
Long-term swelling of the outer lining of the eyes may occur in those with chronic allergies or asthma. It is called vernal conjunctivitis . It is most common in young males, and most often occurs during the spring and summer.
Vernal conjunctivitis
Vernal conjunctivitis is long-term (chronic) swelling (inflammation) of the outer lining of the eyes. It is due to an allergic reaction.
Possible Complications
There are no serious complications.
When to Contact a Medical Professional
Call your provider if:
- You have symptoms of allergic conjunctivitis that do not respond to self-care steps and over-the-counter treatment.
- Your vision is affected.
- You develop eye pain that is severe or becoming worse.
- Your eyelids or the skin around your eyes becomes swollen or red.
- You have a headache in addition to your other symptoms.
References
Rubenstein JB, Tannan A. Allergic conjunctivitis. In: Yanoff M, Duker JS, eds. Ophthalmology . 4th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 4.7.
Stock EL, Meisler DM. Vernal keratoconjunctivitis. In: Tasman W, Jaeger EA, eds. Duane's Ophthalmology. Philadelphia, PA: Lippincott Williams & Wilkins; 2013:vol 4;chap 9.
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Eye - illustration
The eye is the organ of sight, a nearly spherical hollow globe filled with fluids (humors). The outer layer or tunic (sclera, or white, and cornea) is fibrous and protective. The middle tunic layer (choroid, ciliary body and the iris) is vascular. The innermost layer (the retina) is nervous or sensory. The fluids in the eye are divided by the lens into the vitreous humor (behind the lens) and the aqueous humor (in front of the lens). The lens itself is flexible and suspended by ligaments which allow it to change shape to focus light on the retina, which is composed of sensory neurons.
Eye
illustration
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Allergy symptoms - illustration
The immune system normally responds to harmful substances such as bacteria, viruses and toxins by producing symptoms such as runny nose and congestion, post-nasal drip and sore throat, and itchy ears and eyes. An allergic reaction can produce the same symptoms in response to substances that are generally harmless, like dust, dander or pollen. The sensitized immune system produces antibodies to these allergens, which cause chemicals called histamines to be released into the bloodstream, causing itching, swelling of affected tissues, mucus production, hives, rashes, and other symptoms. Symptoms vary in severity from person to person.
Allergy symptoms
illustration
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Conjunctivitis - illustration
Allergy-causing substances like pollen and dander may cause dilatation of blood vessels in the conjunctiva, the membrane covering the eye. The resulting reddening of the eyes is called allergic conjunctivitis, and is usually accompanied by itching and tearing.
Conjunctivitis
illustration
-
Eye - illustration
The eye is the organ of sight, a nearly spherical hollow globe filled with fluids (humors). The outer layer or tunic (sclera, or white, and cornea) is fibrous and protective. The middle tunic layer (choroid, ciliary body and the iris) is vascular. The innermost layer (the retina) is nervous or sensory. The fluids in the eye are divided by the lens into the vitreous humor (behind the lens) and the aqueous humor (in front of the lens). The lens itself is flexible and suspended by ligaments which allow it to change shape to focus light on the retina, which is composed of sensory neurons.
Eye
illustration
-
Allergy symptoms - illustration
The immune system normally responds to harmful substances such as bacteria, viruses and toxins by producing symptoms such as runny nose and congestion, post-nasal drip and sore throat, and itchy ears and eyes. An allergic reaction can produce the same symptoms in response to substances that are generally harmless, like dust, dander or pollen. The sensitized immune system produces antibodies to these allergens, which cause chemicals called histamines to be released into the bloodstream, causing itching, swelling of affected tissues, mucus production, hives, rashes, and other symptoms. Symptoms vary in severity from person to person.
Allergy symptoms
illustration
-
Conjunctivitis - illustration
Allergy-causing substances like pollen and dander may cause dilatation of blood vessels in the conjunctiva, the membrane covering the eye. The resulting reddening of the eyes is called allergic conjunctivitis, and is usually accompanied by itching and tearing.
Conjunctivitis
illustration
Review Date: 8/20/2016
Reviewed By: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.