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Other Names:
Urticaria, Angioedema

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Hives are raised, intensely itchy and red areas on the surface of the skin. They are usually an allergic reaction to food or medicine. Angioedema is a more serious condition characterized by sudden and severe swelling of face, arms, legs, genitalia and airways. Hives are a common occurrence in people with other allergies like hay fever.

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  • Idiopathic - cause unknown
  • Medications
    • e.g. penicillin, aspirin, ibuprofen (Advil, Motrin), angiotensin-converting enzyme (ACE) inhibitors and antibiotics containing sulfa and opiates.
  • Foods
    • e.g. shellfish, fish, nuts, eggs and milk
  • Allergens
    • e.g. pollen, animal dander, latex and insect stings.
  • Antigen/Antibody Reaction
    • e.g. blood transfusions, lupus, infectious mononucleosis, leukemia, cancer, certain thyroid disorders, hepatitis A or B, cold.
  • Others
    • e.g. emotional stress, exposure to extreme cold, sun or heat, excessive sweating, exercise

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  • Raised, itchy, red areas of various sizes that occur in clusters on areas of the body where clothes rub your skin.
  • These areas may appear or disappear suddenly and rapidly.
  • They have well defined margins, enlarge and join together to form larger areas.
  • Abdominal cramping as a result of swelling of abdominal organs
  • Difficulty breathing due to swelling of the airway
  • Loss of voice due to swelling of the vocal cords

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The intense itching of hives can be uncomfortable and frustrating. However, if the swelling occurs inside the throat or tongue, airways can be blocked leading to difficulty breathing, dizziness or unconsciousness. This can be a life threatening even fatal condition (anaphylactic shock).

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What You Can Do

  • Emergency Treatment
    • Call 911 if there is if a severe attack of hives occurs or if there is difficulty breathing, choking, wheezing, sudden tightness in your chest or throat, swelling of face or tongue, dizziness or unconsciousness. You may require an immediate injection of adrenaline followed by a slow intravenous infusion of anti-histamine to control the symptoms
  • Medications
    • Non-prescription medications like diphenhydramine (Benadryl), chlorpheniramine (Chlor-Trimeton), clemastine (Tavist) and loratadine (Claritin, Alavert)
    • Prescription medications like fexofenadine (Allegra), cetirizine (Zyrtec) and hydroxyzine (Hyzine). Oral corticosteroid drugs such as oral prednisone can help reduce swelling, redness and itching.
  • General Measures
    • Take a cold shower or soak in a cool bath
    • Apply cool compresses to the affected area
    • Wear loose, soft, cool and light clothing
    • Avoid itching and further irritating the affected area
    • Apply calamine lotion
    • Take anti-histamines orally to help relieve the symptoms
  • Prevention
    • Avoid wearing tight fitting clothes
    • Avoid taking hot baths or showers
    • Avoid foods, medications and situations that might trigger the attack of hives
    • Read the labels on foods and keep a note of those substances that might have triggered an attack in the past.

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