Allergy Overview
Allergic reaction occurs when your immune system reacts to something that’s usually harmless. Those triggers are called “allergens” and include pollen, mold, animal dander, certain food components, chemicals and even perfume.
According to Web MD, Allergies are very common and at least 1 in 5 Americans suffer from an allergy.
What Happens During an Allergic Reaction?
It starts when you come into contact with a trigger that you inhale, swallow, or get on your skin.
In response, your body starts to make a protein called IgE, which grabs onto the allergen. Then histamine and other chemicals get released into the blood. That causes the symptoms you notice.
What Are the Symptoms?
Your symptoms depend on how you’re exposed — through the air, your skin, food, or through an insect sting.
If you’ve got a nasal or skin allergy, common symptoms include:
- Itchy, watery eyes
- Sneezing
- Itchy, runny nose
- Rashes
- Feeling tired or ill
- Hives (a rash with raised red patches)
Food allergies can also cause stomach cramps, vomiting, and diarrhea.
If an insect sting was the trigger, you’ll have swelling, redness, and pain where it stung you.
Symptoms can range from mild to severe. Most go away shortly after the exposure stops.
Mild ones may be almost unnoticeable. You might just feel a little “off.”
Moderate symptoms can make you feel ill, as if you’ve got a cold or even the flu.
Severe allergic reactions are extreme.
Is It Anaphylaxis?
The most severe allergic reaction is called anaphylaxis. It affects your whole body. Symptoms can include:
- Hives and itching all over
- Wheezing or shortness of breath
- Hoarseness or tightness in the throat
- Tingling in the hands, feet, lips, or scalp
Anaphylaxis is life-threatening, so call 911 right away. If you have an epinephrine auto-injector, use it and repeat after 5 to 15 minutes if your symptoms haven’t improved. You’ll still need medical care right after you give yourself the shots, even if your symptoms seem to stop, because a delayed reaction could still happen.
Is It an Allergy or an Intolerance?
Food allergies or food intolerances affect nearly everyone at some point. People often have an unpleasant reaction to something they ate and wonder if they have a food allergy.
Milk Allergy: If you suffer from a milk allergy, strictly avoiding milk and food containing milk and milk products is the only way to prevent a reaction, which can include immediate wheezing, vomiting, and hives.
Casein Allergy: If a glass of milk or slice of pizza causes swollen lips, hives, or other symptoms, you may have an allergy to casein, a protein in milk. Another milk protein associated with allergies is whey. Some people are allergic to both casein and whey.
Egg allergies: are more common in children than in adults. Reactions range from mild to severe.
Wheat Allergy: It can be a challenge to avoid wheat because it’s in so many things.
Nut Allergy: If you suffer from a nut allergy, strictly avoiding nuts, including peanuts and tree nuts like cashews and walnuts, and food containing nuts is the only way to prevent a reaction.
Fish Allergy: If you’re allergic to one kind of fish, your doctor may have told you to avoid others. Here’s what to look out for.
Shellfish Allergy: If you’re allergic to one type of shellfish, you may have problems with others. Take these steps to make sure you don’t have an allergic reaction.
Sulfite Sensitivity: Sulfites are a group of sulfur-based compounds that may occur naturally or may be added to food as an enhancer and preservative. The FDA estimates that one out of 100 people is sensitive to the compounds.
Soy Allergy: If all you needed to do for a soy allergy was skip the soy sauce and tofu, life would be a breeze! But soybeans are a big part of processed foods, too.
Skin Allergies
Contact Dermatitis: Something touches your skin, and your immune system thinks it’s under attack. It overreacts and sends antibodies to help fight the invader, called an allergen. The result is a red, itchy rash where the substance landed.
Hives: (Urticaria) and AngioedemaHives, also known as urticaria, are an outbreak of swollen, pale red bumps, patches, or welts on the skin that appear suddenly — as a result of allergies, or for other reasons. In angioedema, the swelling happens under the skin, not on the surface.
Allergies to Poison Ivy, Oak, and SumacPoison ivy, poison oak, and poison sumac are plants that contain an irritating, oily sap called urushiol. Urushiol triggers an allergic reaction when it comes into contact with skin, resulting in an itchy rash, which can appear within hours of exposure or up to several days later.
Allergies to Insect Stings: Bee, wasp, yellow jacket, hornet, or fire ant stings are the insect stings that most often trigger allergies. Most people are not allergic to insect stings and may mistake a normal sting reaction for an allergic reaction.
Can You Be Allergic to the Sun? Most people’s skin will burn if there is enough exposure to ultraviolet radiation. However, some people burn particularly easily or develop exaggerated skin reactions to sunlight.
Cosmetic Allergies: Some beauty products can cause skin irritation or allergic reactions. Certain ingredients used in cosmetics, such as fragrances and preservatives, can act as allergens, substances that trigger an allergic reaction.
Nickel Allergy: A nickel allergy is a skin reaction that develops after exposure to nickel or items containing the metal.
Other Allergies
Eye Allergies: Millions of Americans have allergies. Most of those millions have symptoms involving their eyes.
Allergic Conjunctivitis (Pink Eye): Conjunctivitis is one of the most common and treatable eye conditions in children and adults.
Drug Allergies: Many medications can cause side effects, and certain ones can trigger allergies.
Aspirin (Salicylate) Allergy: If you’re allergic to chemicals called salicylates, you may need to avoid certain foods, medicines, and other products.
Penicillin Allergy: Since the 1940s, penicillin has been a go-to drug to clear up infections caused by bacteria. But some people get a bad reaction from taking it.
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