Hives are raised, red welts,often itchy, on the surface of the skin. They are associated with an allergic reaction to food, medicine and very commonly insect stings.
Causes, incidence, and risk factors
When you have an allergic reaction to a substance, your body releases histamine and other chemicals into your bloodstream. This causes itching, swelling, and other symptoms. Hives are a common reaction, especially in people with other allergies such as hay fever.
When swelling or welts occur around the face, especially the lips and eyes, it is called angioedema. Swelling from angioedema can also occur around your hands, feet, and throat.
Many substances can trigger hives, including:
- Animal dander (especially cats)
- Insect stings/bites
- Shellfish, fish, nuts, eggs, milk, and other foods
Hives may also develop as a result of:
- Extreme cold or sun exposure
- Emotional stress
- Excessive perspiration
- Illness (including lupus, other autoimmune diseases and leukemia)
- Infections such as mononucleosis
- Severe itching
- Swelling of the surface of the skin into red- or skin-colored welts (called wheals) with clearly defined edges
The hives may get bigger, spread, and join together to form larger areas of flat, raised skin.
A true hive comes and goes.They can also change shape, disappear, and reappear within minutes or hours. When you press the center of a hive, it turns white. This is called blanching.
When swelling or welts occur around the face, especially the lips and eyes this is specifically called angiodema Swelling from angiodema can also be experienced on your hands, feet, and throat.
Your GP can tell if you have hives by looking at your skin.
If you have a history of an allergy, then the diagnosis is even more obvious.
Occasionally, skin or blood tests are done to confirm that you had an allergic reaction and to test for the substance that caused the allergic response. A skin biopsy can confirm the diagnosis.Treatment may not be needed if the hives are mild. They can disappear on their own. However to reduce swelling and itching it may be helpful to take the following steps
- Avoid hot baths or showers.
- Avoid irritating the area with tight-fitting clothing, particularly synthetics.
- Use mild natural soaps and bathe gently, rinsing thoroughly in warm, not hot water Click here to read about a recommended soap
- If your reaction is severe, especially if the swelling involves your throat, you will require immediate attention by a Medical professional. Consult your GP straight away Hives in the throat can block your airway, making it difficult to breathe.
Hives can be uncomfortable, but they generally are harmless and disappear on their own. In most cases, the exact cause of hives cannot be identified.
- Anaphylaxis a life-threatening, whole-body allergic reaction that causes breathing difficulty
- Swelling in the throat can lead to life-threatening airway blockage
Call 999 if you experience the following:
- Shortness of breath
- Tightness in your throat
- Tongue or face swelling
Call your GP or Nurse if the hives are severe, uncomfortable, and do not respond to self-care measures.
- Avoid exposure to substances that give you allergic reactions.
- Don’t wear tight-fitting clothing and avoid hot baths or showers just after an episode of hives. These can both cause the hives to return.
- If in doubt always consult your GP
Filed under Eczema treatment