Font Size

Hives and Angioedema (cont.)

Hives and Angioedema Causes

Hives and angioedema are reactions of the skin to histamine and other chemicals such as bradykinin, leukotriene C4, and prostaglandin D2. These chemicals act on blood vessels and other tissues to produce the clinical signs of hives and angioedema. This process is often, although not always, due to an allergic reaction.

There are many causes of hives and angioedema. At least half the time, the specific cause cannot be determined. When the cause of a medical condition is not known, it is termed idiopathic. Idiopathic hives and angioedema are very common.

Some of the more common triggers of hives and angioedema include the following:

  • Infections such as viral illnesses, especially in children
  • Allergies to food, medications, cosmetics, soaps, and detergents
  • Insect bites and stings
  • Transfusions of blood or blood products
  • Emotional and physical stress
  • Physical agents such as sunlight, heat, cold, water, or pressure
  • Exercise
  • Allergies to animals, such as pet dander

Chronic hives are hives that lasts longer than 6 weeks. This can happen to anyone, but it is most common in women who are 40 to 60 years of age. Chronic hives can last for months or even years, but this is unusual. Although anyone can get hives, some people are at greater risk.

Risk factors for hives and angioedema include the following:

  • A previous case of hives or angioedema
  • A previous allergic reaction
  • Family members who have hives or angioedema
Medically Reviewed by a Doctor on 6/22/2015

Must Read Articles Related to Hives and Angioedema

Allergic Reaction
Allergic Reaction An allergic reaction is an overreaction to a harmless substance. Symptoms and signs of an learn more >>
Eczema Eczema is a term frequently used to describe any sort of dermatitis. Causes of eczema is generally accepted to be genetically inherited. Common triggers of atop...learn more >>
Rash A rash is a visible skin outbreak. Examples of noninfectious rashes include eczema, psoriasis, contact dermatitis, seborrheic dermatitis, rosacea, hives, and al...learn more >>

Patient Comments & Reviews

The eMedicineHealth doctors ask about Hives and Angioedema:

Hives - Causes

What caused your hives?

Hives - Describe Your Experience

Please describe your experience with hives.

Hives - Home Remedies

What home remedies have been effective for your hives?

Hives - Treatment

What kind of treatment are you getting for your hives and angioedema?

Hives - Prevention

What strategies do you use to try to prevent hives?

Hives - Diagnosis

How were your hives diagnosed?

Read What Your Physician is Reading on Medscape

Angioedema »

Angioedema is a subcutaneous extension of urticaria, resulting in deep swelling within subcutaneous sites.

Read More on Medscape Reference »

Medical Dictionary