Warning Signs of a Hereditary Angioedema Attack

Learn the signs and symptoms that could signal an impending episode of HAE.

Warning Signs of a Hereditary Angioedema Attack

Hereditary angioedema, also called HAE, is a rare genetic disorder that affects an estimated 6,000 to 10,000 people in the United States. People who have HAE experience recurring episodes of severe swelling that can affect any part of the body—the face, hands and feet, genitals and the gastrointestinal tract are the most commonly reported areas. HAE attacks can also cause swelling in the throat and airways, a potentially life-threatening situation that requires emergency medical care and claims a number of lives every year.

Attacks or episodes are sometimes referred to as “acute attacks” or “acute HAE.” Acute is a word used in medicine to describe conditions or symptoms that are severe and sudden in onset.

When do HAE attacks occur?
Episodes of acute hereditary angioedema do not follow a consistent pattern and can be difficult to predict. The areas of the body affected, the severity of symptoms and the duration of symptoms vary from person to person, and episode to episode. Some people experience attacks more frequently than others.

While symptoms do not follow a predictable pattern, some patients report experiencing specific symptoms in the 24 hours leading up to an attack. These include:

  • Fatigue
  • Muscle aches
  • Non-itching red rash
  • Tingling in the area that will be affected
  • Abdominal pain, nausea and other gastrointestinal symptoms

These symptoms are not always followed by an attack, and it is not yet known how common or frequent these symptoms are in patients with HAE. Like other HAE symptoms, these vary between patients, and are not considered a reliable way to predict attacks.

However, in at least one study, a large percentage of people with HAE reported that they could feel when an attack is in the near future.

What can triggers an HAE attack?
Though most HAE episodes are not correlated with any identifiable trigger, some episodes are triggered by specific events. A list of known possible triggers for HAE episodes includes:

  • Mental stress
  • Physical exertion
  • Surgery
  • Dental procedures
  • Minor traumas
  • Illness (for example, the flu)

Certain medications may also cause more frequent HAE attacks and more severe symptoms. These include medications that contain estrogen, such as oral contraceptives and hormone replacement therapy, and ACE inhibitors, a medication used to treat high blood pressure.

Women with HAE also report more frequent HAE episodes during menstruation, during pregnancy and while breastfeeding.

Treating HAE attacks
There is no cure for HAE, but there are a number of treatment options are available. Because symptoms, frequency and severity vary from person to person, it is important that you work with your healthcare provider to build a treatment plan that meets your unique needs as a patient.

Treatment for HAE falls into two broad categories, treatments that reverse acute attacks when they occur, and treatments that prevent attacks from occurring (these are called prophylactic treatments). Prophylactic treatments can be either short term or long term. Short-term prophylactic treatments may be prescribed prior to a surgery or dental work, during pregnancy or during periods of stress, to prevent an attack triggered by these events. Long-term prophylactic treatments are usually prescribed to patients who experience frequent and severe symptoms.

There are a number of treatments taken to reverse acute attacks when they occur. These treatments are taken by a subcutaneous injection or through an intravenous infusion, but can be self-administered once you have had training by a healthcare provider.

Medically reviewed in February 2018.

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