Preventing HAE Attacks

Although attacks of hereditary angioedema (HAE) are often unpredictable. Some potential triggers have been identified:

• Emotional or psychological stress
• Physical stress (eg, an injury, surgery, giving birth, or even dental procedures)
• Physiologic stress (eg, viral or bacterial infections including Helicobacter pylori, which also causes stomach ulcers)
• Medications, such as ACE inhibitors (for high blood pressure) or oral contraceptives

If you have HAE,  avoid or minimize your exposure to these triggers as much as possible. Talk to your doctor, if you are having frequent attacks or know that you will be exposed to a potential trigger—for example, before a dental procedure. Physicians who are experienced in the treatment of HAE are familiar with short- and long-term prophylactic (PRO fill ACK tick) therapy. This type of preventive therapy is used to cut down on the frequency of attacks or to reduce the risk of an attack when the person will be exposed to a known trigger, such as childbirth or surgery.

FACT : HAE attacks can occur anywhere in the body. The most serious attacks grip the voice box.

Long-term Preventive Therapy: To help prevent attacks, your doctor may prescribe medications that are known as androgens (ANN droe jenz). Androgens are male hormones. Those androgens that are most commonly prescribed for HAE include the attenuated (uh TEN yoo ATE ed) androgens danazol, stanazolol, and oxandrin. "Attenuated" means that the male hormone is not as potent as the male hormone testosterone. Still, these drugs are rarely appropriate for children and can have side effects that are unattractive to women.

Antifibrinolytics are medications that are used less often than attenuated androgens in the treatment of HAE. These include tranexamic acid (TA) and epsilon-aminocaproic acid (EACA). Because they can have highly undesirable side effects, however, their use is generally limited to people who suffer frequent and/or severe attacks and cannot tolerate other medications.

As you would with any medicine, discuss your options with your physician.

Short-term Preventive Therapy: Short-term prophylaxis before a dental procedure or surgery is often appropriate. Where available, C1-INH infusions can be given 24 hours before a procedure or just prior to it. C1-INH has been available in Europe for 25 years. If C1-INH is not available, physicians may use antifibrinolytics or attenuated androgens. If so, these medications are usually started 5 days before the procedure and continued for 2 days afterward.

Monitoring of “Trigger” Medications: Pay careful attention to patterns of attacks and identify any medications (such as contraceptives, hormone replacement therapy, ACE inhibitors) that may contribute to the onset of your HAE attacks. Your physician can counsel you in the use of such medications and, in some cases, will be able to steer you to alternative therapies.

Other Treatments: Several types of medication for the treatment of HAE and/or the prevention of attacks are currently under investigation in the United States and around the world. Because these medications have not been approved by the US Food and Drug Administration (FDA), these investigational drugs are only available in the United States for people who are part of clinical research trials.

One class of therapy available in clinical research trials is C1-INH. It is a concentrate that replaces the missing protein that causes HAE. C1-INH concentrate replacement therapy has been used in Europe for more than 25 years, but has not yet been approved in the United States.

Other medications that are being tested for their effectiveness in the treatment of HAE are in classes of medications called bradykinin-2 (or BK-2) receptor antagonists and kallikrein inhibitors. These medications do not replace the missing C1-INH protein, but may be involved in the cascade of reactions that lead to the swelling associated with HAE.