Angioedema (AE) is a sudden swelling of the eyelids, lips, lobes of ears, external genitalia, skin, and other parts of the body. AE can happen by itself. It usually begins during the night and is found on awakening. It can happen with hives and other allergic reactions. Attacks can be mild and annoying, or life-threatening if the air passages swell. AE generally occurs in a short time period (over minutes to hours) and gets better in 24 to 48 hours. It usually does not cause any serious problems.

There are 2 different kinds of AE:

  • Allergic AE.

  • Nonallergic AE.

  • There may be an overreaction or direct stimulation of cells that are a part of the immune system (mast cells).

  • There may be problems with the release of chemicals made by the body that cause swelling and inflammation (kinins). AE due to kinins can be inherited from parents (hereditary), or it can develop on its own (acquired). Acquired AE either shows up before, or along with, certain diseases or is due to the body's immune system attacking parts of the body's own cells (autoimmune).



  • AE due to allergic reactions are caused by something that causes the body to react (trigger). Common triggers include:

  • Foods.

  • Medicines.

  • Latex.

  • Direct contact with certain fruits, vegetables, or animal saliva.

  • Insect stings.


  • Mast cell stimulation may be caused by:

  • Medicines.

  • Dyes used in X-rays.

  • The body's own immune system reactions to parts of the body (autoimmune disease).

  • Possibly, some virus infections.

  • AE due to problems with kinins can be hereditary or acquired. Attacks are triggered by:

  • Mild injury.

  • Dental work or any surgery.

  • Stress.

  • Sudden changes in temperature.

  • Exercise.

  • Medicines.

  • AE due to problems with kinins can also be due to certain medicines, especially blood pressure medicines like angiotensin-converting enzyme (ACE) inhibitors. African Americans are at nearly 5 times greater risk of developing AE than Caucasians from ACE inhibitors.


Allergic symptoms:

  • Non-itchy swelling of the skin. Often the swelling is on the face and lips, but any area of the skin can swell. Sometimes, the swelling can be painful. If hives are present, there is intense itching.

  • Breathing problems if the air passages swell.

Nonallergic symptoms:

  • If internal organs are involved, there may be:

  • Nausea.

  • Abdominal pain.

  • Vomiting.

  • Difficulty swallowing.

  • Difficulty passing urine.

  • Breathing problems if the air passages swell.

Depending on the cause of AE, episodes may:

  • Only happen once (if triggers are removed or avoided).

  • Come back in unpredictable patterns.

  • Repeat for several years and then gradually fade away.


AE is diagnosed by:

  • Asking questions to find out how fast the symptoms began.

  • Taking a family history.

  • Physical exam.

  • Diagnostic tests. Tests could include:

  • Allergy skin tests to see if the problem is allergic.

  • Blood tests to diagnose hereditary and some acquired types of AE.

  • Other tests to see if there is a hidden disease leading to the AE.


Treatment depends on the type and cause (if any) of the AE.


  • Allergic types of AE are treated with:

  • Immediate removal of the trigger or medicine (if any).

  • Epinephrine injection.

  • Steroids.

  • Antihistamines.

  • Hospitalization for severe attacks.


  • Mast cell stimulation types of AE are treated with:

  • Immediate removal of the trigger or medicine (if any).

  • Epinephrine injection.

  • Steroids.

  • Antihistamines.

  • Hospitalization for severe attacks.

  • Hereditary AE is treated with:

  • Medicines to prevent and treat attacks. There is little response to antihistamines, epinephrine, or steroids.

  • Preventive medicines before dental work or surgery.

  • Removing or avoiding medicines that trigger attacks.

  • Hospitalization for severe attacks.

  • Acquired AE is treated with:

  • Treating underlying disease (if any).

  • Medicines to prevent and treat attacks.


  • Always carry your emergency allergy treatment medicines with you.

  • Wear a medical bracelet.

  • Avoid known triggers.


  • You get repeat attacks.

  • Your attacks are more frequent or more severe despite preventive measures.

  • You have hereditary AE and are considering having children. It is important to discuss the risks of passing this on to your children.


  • You have difficulty breathing.

  • You have difficulty swallowing.

  • You experience fainting.

This condition should be treated immediately. It can be life-threatening if it involves throat swelling.