- Angioedema is a type of swelling that affects the deeper layers of the skin. The swelling is sometimes accompanied by hives, which are red, itchy welts that develop on the surface of the skin.
- Angioedema and hives are often triggered by an allergic reaction to certain foods, medications, insect bites, or pollen.
- Treatment for angioedema isn’t always required, but medications may help relieve itching and swelling as well as other symptoms.
Angioedema is a form of severe swelling beneath the skin’s surface. In some cases, the swelling occurs along with the appearance of hives. This is why angioedema is sometimes referred to as “giant hives.” Hives are itchy, red welts that develop on the surface of the skin.
Both angioedema and hives are typically caused by an allergic reaction to food or medication. Other substances, such as pollen, pet dander, and insect bites, may also trigger angioedema. In very rare cases, the swelling can be a symptom of a more serious health condition, such as Hodgkin’s disease. Some areas of the body, such as the face and limbs, are more prone to swelling than others.
When angioedema is passed from a parent to a child through genetic transmission, the condition is known as hereditary angioedema. Hereditary angioedema has different causes, symptoms, treatments, and complications than acquired angioedema.
Angioedema isn’t a serious medical condition and doesn’t leave any lasting marks. It usually goes away on its own, even without treatment.
The most common symptom of angioedema is swelling beneath the surface of the skin. It may occur on the feet, hands, eyes, and lips. In more severe cases, the swelling can spread to other parts of the body. Angioedema may or may not be accompanied by swelling and welts on the surface of the skin.
Additional symptoms of angioedema may include stomach cramping and discolored patches or rash on the hands, arms, and feet. In rare cases, people with angioedema may experience a swollen throat, hoarseness, and difficulty breathing.
Call 911 or go to an emergency room right away if you’re having trouble breathing. This may be a sign of a serious medical condition that requires prompt treatment.
Angioedema is typically the result of an adverse allergic reaction. When you have an allergic reaction, your body produces histamine, which makes your blood vessels swell.
The following allergens can trigger angioedema:
- insect bites
- poison oak or ivy
- animal dander
- certain types of foods
Angioedema may also develop as a result of an infection or illness, such as lupus or leukemia. Hereditary angioedema occurs in people with a family history of the condition.
Certain factors can increase your risk of developing angioedema. These include:
- a previous occurrence of angioedema or hives
- a previous allergic reaction
- a family history of angioedema or hives
- sudden temperature changes
- stress or anxiety
Your doctor will perform a physical exam and ask you about your symptoms and past medical history. During the exam, your doctor will examine your areas of swelling and your welts if any are present. They may also listen to your breathing to see if your throat has been affected. It’s important to tell your doctor if you’ve recently been exposed to certain substances that have triggered an allergic reaction in the past. This may help your doctor determine the specific cause of your reaction.
Your doctor will perform a series of blood tests if hereditary angioedema is suspected. These may include:
- C1 esterase inhibitor test
- complement components C2 and C4
These tests measure the levels of certain proteins in the blood. Low levels can indicate a health problem related to inflammation and swelling.
People with mild symptoms of angioedema may not need treatment. However, those with moderate or severe symptoms may require certain medications to help relieve intense itching and swelling. These medicines can include:
- antihistamines, such as loratadine (Claritin) and cetirizine (Zyrtec)
- anti-inflammatory medications (e.g., prednisone, Solumedrol)
Certain home remedies may also help relieve symptoms. These include:
- applying cool, wet compresses to help soothe the skin and prevent scratching
- adding baking soda to a cool bath to relieve itching
- wearing loose cotton clothing to avoid further skin irritation
In most cases, angioedema is a harmless condition and will disappear within one to three days. However, angioedema can be dangerous when the swelling occurs near the throat. A swollen throat or tongue can block your airway and make it very difficult to breathe. Severe angioedema may also cause anaphylaxis, a life-threatening allergic reaction.
The best way to prevent angioedema is to avoid known and suspected allergens. You should also try not to irritate areas on the body that have been previously affected. Taking these preventive measures can help lower your risk of having another episode in the future.