Pink Eye: Allergic Conjunctivitis

Conjunctivitis is an irritation of the conjunctiva, a thin, clear membrane covering the eyeball and the inside of the eyelids. Conjunctivitis is bacterial, viral or allergic. While contagious forms of conjunctivitis result from bacterial or viral infection, allergic conjunctivitis is never contagious.

Allergic conjunctivitis symptoms may include:

• bloodshot eyes
• eye pain
• itchy eyes
• swelling in the eye area
• watery eyes.

Allergic conjunctivitis has five major subcategories:

• atopic keratoconjunctivitis (AKC)
• giant papillary conjunctivitis (GPC)
• perennial allergic conjunctivitis (PAC)
• seasonal allergic conjunctivitis (SAC)
• vernal keratoconjunctivitis (VKC).

Although all types of allergic conjunctivitis can be annoying and uncomfortable, none are dangerous and rarely affect eyesight.

Allergic Conjunctivitis Triggers

Allergic conjunctivitis can be seasonal or chronic. A variety of allergens trigger symptoms. Some common triggers for allergic conjunctivitis include:

• animal skin or saliva
• cockroaches
• cosmetics
• dust mites
• grass, tree and weed pollens
• medications for skin
• perfume
• pollutants in the air
• smoke.

Avoiding triggers will bring your eyes relief:

• If cosmetics or perfumes bother you, using hyper-allergenic brands might help offset symptoms.
• If you are allergic to smoke, avoid places where people are smoking and ask friends and family not to smoke in your home.
• Pollen exposure can be reduced by staying indoors when the pollen count is high. Closing windows and doors as well as using your air conditioner helps.
• You can reduce dust mite exposure by washing all bedding frequently in hot water and using a machine dryer. Hypoallergenic covers for bedding also help keep dust mites away.

Risk Factors for Allergic Conjunctivitis

Although no one knows the exact cause of allergic conjunctivitis, some known risk factors include:

• Age and Gender: Males are more likely than females to develop VKC. Boys under the age of 10 are the most likely to develop VKC. Symptoms usually peak before puberty and then diminish.
• Ethnicity: People with African and Indian decent and dark skin are more likely to develop VKC than those in the general population.
• Geographic Location: VKC is most common in tropical and temperate climates including Africa, the Mediterranean and the Middle East.

Family history is also a risk factor for all types of allergic conjunctivitis.

Treating Allergic Conjunctivitis

For some people, symptoms of allergic conjunctivitis are mild and don't require any treatment. You can put a cold washcloth on your eyes for relief of mild symptoms, or try over-the-counter lubricating eye drops. If your symptoms are bothersome and avoiding your triggers isn't bringing enough relief, your doctor can help you find the best treatment. Some of the ways allergic conjunctivitis is treated include:

• anti-inflammatory eye drops
• antihistamine eye drops
• antihistamine pills
• eye drops containing medicine that stops mast cells from releasing histamine
• mild ophthalmic steroids (for severe reactions).

If your allergic conjunctivitis is flaring up, doctors suggest that you do not wear contact lenses until your eyes are better.

Resources

American Academy of Family Physicians. (2008). Allergic conjunctivitis. Retrieved March 22, 2009, from the FamilyDoctor.org Web site: http://familydoctor.org/online/famdocen/home/common/allergies/basics/678.html.

HowStuffWorks, Inc. (2009). Allergic conjunctivitis. Retrieved March 22, 2009, from the HowStuffWorks.com Web site: http://healthguide.howstuffworks.com/allergic-conjunctivitis-dictionary.htm.

Majmudar, P., M.D. (2008). Conjunctivitis, allergic. Retrieved March 22, 2009, from the eMedicine.Medscape.com Web site: http://emedicine.medscape.com/article/1191467-overview.