Angioedema

Overview

Angioedema is sudden swelling that happens deep beneath the skin and in the soft tissues, rather than on the surface. It most often affects loose-tissue areas such as the eyelids, lips, tongue, throat, hands, feet, and genitals. The swelling can come on quickly, may feel tight or painful rather than itchy, and can be alarming when it involves the face.

Angioedema frequently occurs together with hives as part of an allergic reaction, but it can also be caused by certain medications or by inherited and acquired conditions that are not allergic. Most episodes are uncomfortable but not dangerous. However, swelling of the tongue, throat, or airway can interfere with breathing and is a medical emergency that needs immediate care.

Common Causes

Angioedema can be allergic or non-allergic. Common causes include:

• Allergic reactions: foods, insect stings, latex, or medications, often with hives. Severe reactions can progress to anaphylaxis.
• Medications: certain blood pressure drugs (ACE inhibitors) and pain relievers can trigger swelling.
• Hereditary angioedema: an inherited condition causing recurrent swelling without hives.
• Acquired non-allergic forms: related to other medical conditions.
• Idiopathic: recurrent swelling with no identified cause.
• Physical triggers: rarely, cold, pressure, or vibration.

Associated Symptoms

Angioedema may appear alone or with other allergic symptoms:

• Hives and itching, when the cause is allergic
• Swelling of the lips, eyelids, or face
• Tongue or throat swelling with a tight or muffled voice
• Difficulty breathing or swallowing if the airway is involved
• Abdominal cramps when the gut is affected, especially in hereditary forms
• A feeling of tightness or burning rather than itch in non-allergic types

Swelling of the tongue, throat, or any difficulty breathing is a warning sign requiring emergency care.

Diagnosis & Evaluation

A clinician evaluates angioedema based on the pattern, triggers, and whether hives are present. Evaluation may include:

• History: recent foods, medications, stings, and whether episodes recur or run in the family.
• Examination: identifying the sites of swelling and checking the airway.
• Medication review: looking for drugs such as ACE inhibitors that can cause angioedema.
• Blood tests: for hereditary or acquired forms when swelling recurs without hives.
• Allergy testing: to identify triggers in allergic angioedema.

Treatment & Management

Treatment depends on the cause and severity, and airway involvement is always treated as an emergency:

• Emergency care: for any throat, tongue, or airway swelling, including epinephrine if the reaction is allergic and severe.
• Antihistamines and corticosteroids: for allergic angioedema with hives.
• Stopping the trigger: avoiding the responsible food or medication; ACE inhibitor angioedema requires stopping that drug under medical advice.
• Specific therapies: targeted medicines for hereditary angioedema, which does not respond to standard allergy drugs.
• Specialist care: referral to an allergist or immunologist for recurrent or unexplained swelling.

People with severe allergic angioedema may be prescribed an epinephrine auto-injector to carry.

Self-Care & Prevention

Whether angioedema can be prevented depends on its cause, but several steps help:

• If a trigger is known, such as a food, medication, or insect sting, avoid it carefully.
• Tell all your healthcare providers about any medication that has caused swelling so it is not prescribed again.
• If you take an ACE inhibitor and develop swelling, seek medical advice rather than continuing it.
• For allergic angioedema, carry any prescribed epinephrine auto-injector and an action plan.
• For hereditary angioedema, follow your specialist's prevention plan and keep prescribed medicines on hand.
• Wear a medical alert bracelet if you have severe or recurrent episodes.

Knowing the warning signs of airway involvement and when to seek emergency care is an essential part of staying safe.

When to See a Doctor

Call emergency services immediately if angioedema involves:

• Swelling of the tongue or throat
• Any difficulty breathing, swallowing, or a tight, muffled voice
• Rapidly spreading swelling with dizziness, fainting, or widespread hives

Use a prescribed epinephrine auto-injector at the first signs of a severe allergic reaction, then seek emergency care. See a doctor promptly for new, recurrent, or unexplained angioedema, or swelling that appears after starting a new medication, so the cause can be identified and the right treatment started.

Related Topics

Frequently Asked Questions

References

1. American Academy of Allergy, Asthma & Immunology (AAAAI). Angioedema.
2. Mayo Clinic. Hives and angioedema — Symptoms and causes.
3. MedlinePlus, U.S. National Library of Medicine. Angioedema.
4. National Organization for Rare Disorders (NORD). Hereditary Angioedema.