Hives: Causes, Symptoms, Diagnosis, Treatment, and Prevention
Several people suffer from hives at some point in their lives. They are also referred to as urticaria, welts, or nettle rash. Hives are usually caused by an allergy to something you have encountered or swallowed, such as food, medicines, pollen, or insect bites. In some cases, the cause of hives is unknown or related to other factors, such as stress, infection, or physical trauma. We will explain what hives are, what causes them, how to recognize them, how to treat them, and how to prevent them in this blog post.
What are hives?
A hive is a raised, red, itchy bump or patch of skin that can vary in size and shape. It can appear anywhere on the body, change location, disappear and reappeare over time. It can last for a few hours or as long as six weeks. Chronic hives last longer than six weeks.
An allergic reaction or a trigger causes the body to release a chemical called histamine, which causes hives. It causes the blood vessels beneath the skin to leak fluid, causing swelling and itching. Hives do not leave scars and are not contagious.
What causes hives?
A common cause of hives is an allergic reaction to something you have encountered or swallowed. Some of the allergens that can trigger hives include:
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Foods, such as nuts, eggs, shellfish, milk, wheat, soy, or strawberries.
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Medications, such as antibiotics, aspirin, ibuprofen, or blood pressure drugs.
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Insect bites or stings, such as from bees, wasps, mosquitoes, or ants.
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Pollen, dust mites, mold, animal dander, or latex.
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Cosmetics, perfumes, detergents, or jewelry.
However, not all cases of hives are caused by allergies. Some other possible causes or triggers of hives include:
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Stress, anxiety, or emotional distress.
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Infections, such as viral infections (e.g., colds), bacterial infections (e.g., strep throat), fungal infections (e.g., candida), or parasitic infections (e.g., worms).
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Physical stimuli, such as heat, cold, sun exposure, pressure, vibration, exercise, or sweating.
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Underlying health conditions, such as autoimmune diseases (e.g., lupus), thyroid disorders (e.g., hyperthyroidism), hormonal changes (e.g., pregnancy), or cancer (e.g., lymphoma).
Sometimes the cause of hives is unknown or cannot be identified. This is called idiopathic urticaria.
What are the symptoms of hives?
In addition to being itchy, hives typically appear as red, raised bumps or patches on the skin. They can range in size from a few millimeters to several centimeters and can have different shapes and patterns. Most commonly, they occur on the face, neck, chest, back, arms, and legs, but can occur anywhere on the body.
Other symptoms that may accompany hives include:
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Burning or stinging sensation on the skin.
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Swelling of the lips, eyes, tongue, throat, or genitals (this is called angioedema and can be a sign of a severe allergic reaction).
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Difficulty breathing, wheezing, coughing, or chest tightness (this is also a sign of a severe allergic reaction).
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Fever, headache, nausea, vomiting, diarrhea, or joint pain (these may indicate an infection or an underlying health condition).
How are hives diagnosed?
Your doctor will examine your skin and look for any signs of hives or angioedema to diagnose hives based on your medical history, your symptoms, and possible exposure to allergens.
Additionally, your doctor may order some tests to rule out other causes of your symptoms or to identify the specific allergen causing your hives. These tests include:
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Blood tests to check for signs of infection, inflammation, or autoimmune diseases.
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Skin tests to check for allergic reactions to specific substances by applying them to your skin and observing for any reactions.
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Allergy tests to check for antibodies to specific allergens in your blood by drawing a sample of your blood and exposing it to different allergens in a laboratory.
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Biopsy to check for any abnormal cells in your skin by taking a small sample of your skin and examining it under a microscope.
How are hives treated?
The main goal of treatment for hives is to relieve the itching and swelling and to prevent any complications from a severe allergic reaction. The treatment options for hives may include:
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Taking antihistamines will block histamine's effects and reduce itching and swelling. Some antihistamines are available over-the-counter, while others require a prescription. Some antihistamines can be taken orally, while others can be applied topically. Diphenhydramine, cetirizine, loratadine, fexofenadine, and hydroxyzine are among the antihistamines available.
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To reduce inflammation and suppress the immune system, corticosteroids can be taken orally, injected, or applied topically. It is usually prescribed for short-term use only for severe cases of hives. Prednisone, methylprednisolone, and triamcinolone are examples of corticosteroids.
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A severe allergic reaction such as wheezing, difficulty breathing, or low blood pressure can be treated with epinephrine. Typically, epinephrine is injected directly into the thigh muscle with an auto-injector device. Epinephrine is a hormone that constricts blood vessels and relaxes airways. Among the auto-injectors that contain epinephrine are EpiPen, Auvi-Q, and Adrenaclick.
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Hives can be treated or prevented from recurring with other medications. A specialist usually prescribes these medications and they require close monitoring. These medications may include antibiotics, antivirals, antifungals, antiparasitics, immunosuppressants, and immunomodulators.
How can hives be prevented?
The best way to prevent hives is to avoid or limit your exposure to any allergens or triggers that cause them. Some of the steps that you can take to prevent hives include:
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Keeping a diary of your symptoms and possible triggers to identify what causes your hives and when they occur.
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Reading the labels of any foods, medications, cosmetics, or other products that you use or consume and avoiding any ingredients that you are allergic to.
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Wearing loose-fitting, breathable clothing and avoiding fabrics that irritate your skin.
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Using mild soap and moisturizer and avoiding harsh chemicals or fragrances on your skin.
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Staying away from extreme temperatures or weather conditions that trigger your hives.
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Managing your stress levels and practicing relaxation techniques such as meditation, yoga, or breathing exercises.
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Seeking medical attention if you have any signs of a severe allergic reaction or an infection.
Summary
A common skin condition called hives causes red, itchy bumps on the skin. An allergic reaction to something you have encountered or swallowed is usually the cause, but it can also be caused by stress, infection, or physical stimulation. Hives can be acute or chronic depending on their duration. Hives can be treated with antihistamines, corticosteroids, epinephrine, or other medications depending on the severity of the condition. You can prevent hives by avoiding or limiting your exposure to allergens or triggers.
