What Is Hereditary Angioedema (HAE)?

HAE is a rare, potentially life-threatening genetic disorder. Stay educated about the disease and keep the conversation going with your doctor about the best treatment plan for you.

About HAE

About HAE

Hereditary angioedema, or HAE, is a rare disease, affecting an estimated 1 in 10,000 to 1 in 50,000 people around the world. HAE can cause attacks of sometimes painful and disabling swelling in the abdomen, face, feet, genitals, hands, and throat.

Defining HAE

HAE is called "hereditary" because literature suggests that about 75% of cases are passed down through families. Still, about 25% of people with HAE have no family history at all. These cases result from a genetic change that happens spontaneously. Once the spontaneous change happens, it can be passed on to children.

HAE attacks often happen without a known trigger. However, they can sometimes be triggered by:

  • Minor trauma (an injury or shock to the body)
  • Stress
  • Dental procedures
  • Infections
  • Surgery
  • Hormonal changes

During an HAE Attack

A protein called plasma kallikrein triggers the production of another protein called bradykinin that may lead to HAE attack symptoms.

  • Your body's levels of activated plasma kallikrein are increased.
  • The increased levels of plasma kallikrein lead to the formation of bradykinin that causes blood vessels to release fluid.
  • Released fluid builds up in various parts of the body, resulting in localized swelling and pain.

Common HAE symptoms include sometimes painful swelling. Swelling in the throat can make breathing difficult, and about 50% of people in a survey of 209 patients experienced at least 1 throat attack.

When untreated, the swelling in an HAE attack usually increases over a 24-hour period and then gradually subsides during the next 48–72 hours. Some people experience attacks that last longer than a week. An HAE attack can also start in one location and then spread to another before resolving.

Treatment Options

Two types of HAE treatments are currently available: preventive and acute.

  • Preventive treatment, also called prophylactic treatment, or prophylaxis, is taken on a regular basis to prevent or reduce the number of HAE attacks. Current guidelines recommend that all patients should be evaluated for long-term preventive treatment at every doctor's visit, or at least once a year.
  • Acute treatment, also known as on-demand treatment, is used to treat the symptoms of an HAE attack.
  • Even with preventive treatment, attacks can happen. Experts recommend that acute treatment be a part of every HAE treatment plan.
  • Treatment of acute HAE attacks should be administered as early as possible in an attack, for all attacks, regardless of location, as soon as they are clearly recognized.

Learn how KALBITOR (ecallantide) works to treat HAE attacks by inhibiting plasma kallikrein.


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Important Safety Information

What is the most important information I should know about KALBITOR?
Serious allergic reactions may happen in some people who receive KALBITOR. These allergic reactions can be life-threatening and usually happen within 1 hour after receiving KALBITOR.

  • KALBITOR should be given to you by a doctor or nurse in a healthcare setting where serious allergic reactions and hereditary angioedema (HAE) can be treated.
  • Symptoms of a serious allergic reaction to KALBITOR can be similar to the symptoms of HAE, the condition that you are being treated for. Your doctor or nurse should watch you for any signs of a serious allergic reaction after treatment with KALBITOR.
  • Tell your doctor or nurse right away if you have any of these symptoms of a serious allergic reaction during or after treatment with KALBITOR:
    • wheezing, shortness of breath, cough, chest tightness, or trouble breathing
    • dizziness, fainting, fast or weak heartbeat, or feeling nervous
    • reddening of the face, itching, hives, or feeling warm
    • swelling of the throat or tongue, throat tightness, hoarse voice, or trouble swallowing
    • runny nose, nasal congestion, or sneezing

Who should not receive KALBITOR?
Do not receive KALBITOR if you are allergic to KALBITOR. Before receiving KALBITOR, tell your doctor if you have ever had an allergic reaction to KALBITOR.

What else should I tell my doctor before I receive KALBITOR?
Tell your doctor if you are pregnant, plan to become pregnant, breast-feeding, or plan to breast-feed. It is not known if KALBITOR will harm your unborn baby or pass into your breast milk.

Tell your doctor about all the medicines you take, including prescriptions and over-the-counter medicines, vitamins, and herbal supplements.

What are the possible side effects?
Common side effects of KALBITOR include headache, nausea, diarrhea, fever, injection site reactions, such as redness, rash, swelling, itching, or bruising, and stuffy nose. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch, or call 1-800-FDA-1088.

Talk to your doctor for more information about your medical condition or treatment.

Please see the Full Prescribing Information, including Boxed Warning and Medication Guide.