When harmful bacteria or viruses attack the body, the immune system responds and sends immune cells to fight the invader. An allergic reaction happens when the immune system overreacts and fights normally harmless substances, known as allergens. Almost anything can cause an itchy allergic reaction, including pollen, food, medicine, and metal.
An itchy allergic reaction can happen anytime. Seasonal allergies typically are caused by the increase of pollen during the spring and fall months. Pollen can come from tress, grass or weeds. Allergy sufferers might experience itchy noses and eyes along with coughing and sneezing because of the pollen in the air.
Year-round allergies are possible for some people. These types of allergic reactions usually are from allergens with which a person comes into contact on a regular or daily basis. Animal dander, household dust and mold can cause an itchy allergic reaction in the eyes and nose.
The skin also can be affected by an itchy allergic reaction. Poison ivy can cause a rash with blisters that can itch. Depending on the severity of the allergy, the rash can be localized or spread over the body. Certain food allergies can also cause patches of itchy, red welts — called hives — to spread over the body.
Preventing an allergic reaction can be difficult, especially if the allergy is caused by a common allergen, such as household dust. Whenever possible, the trigger should be avoided. Triggers are the antigen that usually starts an allergic reaction. People who have a food allergy should avoid the food that causes their allergic reaction by being conscious of ingredients in recipes, and people who have grass allergies should stay indoors when pollen counts are high, to keep the allergic reaction to a minimum.
When a trigger is unavoidable, over-the-counter allergy medicines can help with itchy allergic reactions. There are a variety of formulas available for different allergy symptoms. For more severe allergies, people might have to take corticosteroids or weekly allergy shots.
Some people might experience anaphylaxis, which is a severe allergic reaction to allergens. Peanut and bee-sting allergies are common severe allergies. Sometimes people who have anaphylactic allergies can stop breathing when they come into contact with the allergen. An epinephrine shot might be needed immediately to save the person’s life. A special epinephrine pen can be prescribed to patients who have severe allergies so they can carry the drug with them wherever they go.
An allergy specialist can pinpoint the things to which a person is allergic by performing a skin test that injects a small amount of different types of allergens into a patient’s skin. There are tests for most allergens, including possible allergies to latex and metal. If the patient is allergic to the allergen, the patient might have an itchy allergic reaction that causes a red welt to rise on the skin.