Angioedema is a condition characterized by swelling beneath the skin or around mucous membranes. It can occur in various parts of the body, including the face, hands, feet, and even the gastrointestinal tract. This swelling is often caused by allergic reactions or medication side effects, but in some cases, the cause is unknown.

Because it often occurs alongside hives, angioedema is sometimes called “giant hives.” While both conditions involve swelling, angioedema affects deeper layers of the skin, whereas hives affect the top two layers.

Symptoms of Angioedema

The hallmark symptom of angioedema is swelling. The most common areas affected include:

• The face (forehead, around the eyes, lips)
• Tongue
• Hands and feet
• Genitals
• Gastrointestinal tract
• Upper airways

In some cases, swelling is accompanied by hives or raised welts, which can be itchy. Other symptoms may include:

• Fainting
• Abdominal cramping
• Dizziness
• Shortness of breath (a medical emergency)

If the swelling affects the airways and causes difficulty breathing, it can be life-threatening. If you experience difficulty breathing, seek emergency medical help immediately.

Types and Causes of Angioedema

Several factors can trigger angioedema, and different types exist based on the underlying cause:

1. Allergic Angioedema

This is the most common type, caused by allergic reactions to:

• Foods (like peanuts, shellfish, or latex)
• Medications (such as antibiotics)
• Insect stings or bites

2. Nonallergic Drug-Induced Angioedema

This occurs when medications trigger angioedema, not through an allergic reaction but through other mechanisms. ACE inhibitors (used to treat high blood pressure) are a common cause of this type.

3. Hereditary Angioedema (HAE)

This less common form is inherited and results from a genetic defect affecting an enzyme in the immune system. HAE tends to appear without any external triggers.

4. Idiopathic Angioedema

In about 40% of cases, the cause of angioedema is unknown. This is called idiopathic angioedema.

5. Acquired Angioedema

This form may develop after an illness, infection, or as part of autoimmune diseases like lupus or lymphoma.

Risk Factors for Angioedema

Certain factors can increase your likelihood of developing angioedema. Some risk factors include:

• Being older
• Smoking
• Having certain medical conditions (e.g., cardiovascular disease or autoimmune diseases)
• A family history of hives or angioedema
• Gender and ethnicity, with women and African Americans being at higher risk

If you have allergies or a previous history of angioedema, you should take extra precautions to avoid known triggers.

Diagnosing Angioedema

If you suspect angioedema, a healthcare provider will perform a physical exam and ask about your symptoms and medical history. They may conduct blood tests to check for hereditary or acquired angioedema, including testing for:

• C1 esterase inhibitors (important for diagnosing hereditary angioedema)
• Complement levels (C2, C4)

These tests help identify underlying conditions that could be triggering your symptoms.

Treatment Options for Angioedema

Treatment depends on the severity of symptoms. Mild cases may resolve without treatment, but moderate to severe cases require medical intervention.

For mild allergic reactions, antihistamines like loratadine (Claritin) or cetirizine (Zyrtec) are common treatments. In more severe cases, epinephrine (EpiPen) may be necessary for acute allergic reactions.

For hereditary angioedema, treatments may include:

• C1 inhibitor concentrate
• Ecallantide or icatibant (for bradykinin-induced angioedema)

Avoiding the substances that trigger the reaction is crucial. In some cases, switching medications may also be necessary.

For comfort, applying cool compresses and wearing loose clothing can alleviate swelling and irritation.

Long-Term Outlook

Most cases of angioedema resolve within a few days, but in rare cases, severe swelling can cause life-threatening complications, especially if it affects the airways. If this happens, immediate medical intervention is critical.

Hereditary angioedema may require ongoing treatment and management. For recurrent cases, medications like C1 inhibitors may be necessary to prevent future episodes.

Preventing Angioedema

The best prevention method for allergic angioedema is avoiding known allergens. If you’ve experienced angioedema before, it’s important to:

• Avoid the substances that caused the reaction
• Use antihistamines or prescribed medications as preventive measures
• Monitor your health regularly if you have a history of allergic reactions

Takeaway

Angioedema is a condition that causes deep swelling under the skin and mucous membranes. While mild cases may resolve quickly, severe angioedema requires urgent medical attention. Understanding the underlying cause can help guide effective treatment and prevent future episodes.

If you experience trouble breathing or significant swelling, seek emergency medical care immediately.