What is urticaria?

Urticaria, or hives, is a condition in which red, itchy, raised areas appear on the skin. Urticaria may last for a short or long time. If it lasts for a short time, the cause is usually an allergic reaction from eating certain foods or taking certain medicines. When urticaria is long-term, the cause is often unknown. Hives vary in size and may come and go. Hives can affect most of the body or just a small area.

What foods commonly cause hives?

Hives are a common reaction to allergies to the following foods:

  • Nuts

  • Peanuts

  • Eggs

  • Fish

  • Shellfish

  • Milk

  • Wheat

  • Soy

What medicines commonly cause hives?

Hives are a common reaction to allergies to the following medicines:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen

  • Antibiotics, especially penicillin and sulfa-based medicines

  • Anticonvulsant or antiseizure medicines

  • Chemotherapies 

  • ACE inhibitors for high blood pressure, such as lisinopril or enalapril

  • Medicines for treating cancer, such as monoclonal antibodies

Other types of hives

Other types of hives include:

  • Dermatographism. Hives caused by scratching or pressure on the skin.

  • Cold-induced. Hives caused by exposure to cold air or water.

  • Solar hives. Hives caused by exposure to sunlight or other light.

  • Exercise-induced hives. These are brought on by physical activity.

  • Chronic urticaria. Recurrent hives with no known cause.

What is angioedema?

Angioedema is an allergic reaction that causes swelling in the deeper layers of skin. It sometimes happens with hives. It's most common on the hands, feet, and face (lips, tongue, and eyes). Angioedema can be serious, and may need immediate medical attention. This is especially true if there is swelling of the tongue, lips, and/or throat. A person who has angioedema may feel as if his or her throat is closing up, making it difficult to breathe.