Nearly half of all men and women suffer from some sort of allergy. Allergies can cause symptoms that affect the skin, sinuses, airways, digestion, and eyes. About 75 percent of people who suffer from allergies have symptoms that affect the eyes. While allergies cannot be completely cured, there are a number of treatments that can help to relieve symptoms.

What are allergies?

An allergy is an exaggerated or oversensitive immune response. Allergies occur when the immune system reacts to a foreign substance that is not harmful, like dust, pollen, and certain foods. The reaction triggers the release of histamines to fight off the allergen, which produces telltale symptoms like itching, swelling, rashes, and hives.

Symptoms of allergies

Allergies are relatively common, but the symptoms vary from person to person. Here are some common symptoms of allergies: 

• Runny nose
• Skin rash 
• Red, swollen, burning eyes 
• Itchy eyes 
• Watering eyes 
• Headache 
• Sinus congestion 
• Coughing and sneezing
• Diarrhea 
• Stomach cramps 
• Vomiting 
• Difficulty breathing

Causes of allergies

Allergic reactions occur when the immune system mistakes a relatively harmless substance for a dangerous invader. The immune system then begins to produce antibodies that are ready to be deployed against a particular allergen. Exposure to that allergen causes the release of immune system chemicals like histamines that are designed to fight off the allergen. These histamines produce an allergic reaction that can affect everything from the skin to the eyes.

Here are just a few of the common triggers that can produce an allergic reaction: 

• Pollen 
• Pet dander 
• Foods like peanuts, wheat, dairy, soy, shellfish, and eggs 
• Medications 
• Insect bites 
• Latex 
• Mold

Treatment of allergies

Allergies cannot be cured, so the best way to "treat" an allergy is to avoid the trigger. When doctors cannot identify the source of the allergic reaction or when it is impossible to avoid the allergen, there are several medications available to treat the symptoms of allergies, including antihistamines and corticosteroids. People with severe allergy symptoms may require treatment with epinephrine. Eye drops can also help relieve eye discomfort due to allergies.

If an allergic reaction severely affects your vision, visit your doctor to check the health of your eyes.