Allergic reactions

Anaphylaxis; Anaphylaxis - first aid

Allergic reactions are sensitivities to substances called allergens that come into contact with the skin, nose, eyes, respiratory tract, and gastrointestinal tract. They can be breathed into the lungs, swallowed, or injected.

Allergic reactions

Allergic reaction can be provoked by skin contact with poison plants, chemicals and animal scratches, as well as by insect stings. Ingesting or inhaling substances like pollen, animal dander, molds and mildew, dust, nuts and shellfish, may also cause allergic reaction. Medications such as penicillin and other antibiotics are also to be taken with care, to assure an allergic reflex is not triggered.

Dermatographism - close-up

Dermatographism is a condition where lightly scratching the skin raises wheals or welts. Histamine is released, which causes the small blood vessels (capillaries) to dilate, producing redness and localized swelling.

Dermatographism on the arm

Dermatographism is a condition where lightly scratching the skin raises wheals or welts. Histamine is released at the site, causing the small blood vessels (capillaries) to dilate, producing redness and localized swelling.

Hives (urticaria) on the arm

Hives (urticaria) are raised, red, itchy welts, seen here on the arm. The majority of urticaria develop as a result of allergic reactions. Occasionally, they may be associated with autoimmune diseases, infections (parasitosis), drugs, malignancy, or other causes.

Hives (urticaria) on the chest

Hives (urticaria) are raised, red, itchy welts, seen here on the chest. The majority of urticaria develop as a result of allergic reactions. Occasionally they may be associated with autoimmune diseases, infections (parasitosis), drugs, malignancy, or other causes.

Hives (urticaria) - close-up

Hives (urticaria) are raised, red, itchy welts. The majority of urticaria develop as a result of allergic reactions. Occasionally, they may be associated with autoimmune diseases, infections (parasitosis), drugs, malignancy, or other causes.

Hives (urticaria) on the trunk

This person has raised, red, itchy welts (urticaria) on the chest and abdomen. The majority of urticaria develop as a result of allergic reactions. Occasionally, they may be associated with autoimmune diseases, infections (parasitosis), drugs, malignancy, or other causes.

Dermatographism on the back

In dermatographism, hives are readily produced if the skin is lightly scratched.

Dermatographism - arm

Wheal formation at the site of light scratching of the skin.

Allergic reactions

Allergic reaction is a sensitivity to a specific substance, called an allergen, that is contacted through the skin, inhaled into the lungs, swallowed or injected. The body's reaction to an allergen can be mild, such as a localized rash, or life-threatening, such as anaphylactic shock.

Blooming flowers and blossoming trees are signs that spring has arrived. But for some people, those blossoms and blooms are also signs that allergy season is under way. And that means months of sniffling, sneezing, and runny eyes ahead. You may know that you have allergies as soon as you step outside on a spring day, eat peanuts, or pet your dog. Signs of an allergy may include trouble breathing, teary eyes, hives, itching, or vomiting after you come in contact with your allergy trigger. Your doctor can also do allergy tests to find out whether you're allergic, and what triggers your allergies. The most common type of allergy test is a skin test. The doctor puts a small amount of different allergy-causing substances under your skin. Then you wait for signs of a reaction, like swelling or redness. You might also have blood tests to check for chemicals that are related to allergies. So, how are allergies treated? There are a few medicines you can buy at your local drugstore or your doctor can prescribe to treat your allergies. Antihistamines prevent histamine chemicals from triggering allergy symptoms. Decongestants shrink swollen blood vessels throughout your body, including inside your nose, perhaps helping you breathe easier. Steroid drugs reduce swelling and inflammation. And Leukotriene inhibitors block the substances that trigger allergies. If your allergy is really bugging you, your doctor may give you allergy shots. When you take allergy shots over time, eventually they can help your body get used to the substance so you don't over-react to it in the future. Usually you can relieve allergies by taking medicine and avoiding whatever it is that triggers them. But in some people, allergies to insect stings or certain foods, like peanuts, cause a life-threatening reaction. This is called anaphylaxis. And if you have a life-threatening allergic reaction, call immediately for emergency medical help.

Considerations

Causes

Symptoms

First Aid

Do Not

When to Contact a Medical Professional

Prevention