Preventive Therapy versus Rescue Therapy for HAE

Treatment for hereditary angioedema focuses on preventing attacks as well as treating attacks when they occur.

Medications that prevent HAE attacks can typically be taken at home, either as an injection or as an oral medication.

Hereditary angioedema (HAE) is a rare genetic disorder that causes episodes of swelling in different areas of the body—most commonly the hands, feet, face, intestinal tract, and airways. This swelling can be painful, especially in the abdomen. It can also be life threatening when it occurs in the airways.

There is no cure for HAE, but there are therapies that can prevent attacks from occurring as well as therapies that can treat attacks when they occur. Both types of therapies are important to the treatment of HAE.

Preventive therapy

As the name implies, preventive therapies are used to prevent attacks from happening. They are also known as prophylactic therapies.

Because HAE attacks have the potential to be life-threatening, preventing attacks is an important focus of treatment for HAE.

There are several preventive therapies available, which fall into two basic categories based on how they work.

  • C1 esterase inhibitors. These medications are typically taken through IV infusions and are typically administered at a healthcare office, although a healthcare provider can teach you how to administer some medications at home. (There is also one that is taken with a self-administered subcutaneous injection.) These therapies work by replacing a protein that is missing or working incorrectly when a person has HAE.
  • Kallikrein inhibitors. These medications decrease production of a protein called plasma kallikrein, which promotes inflammation and becomes too active when a person has HAE. These medications can typically be taken at home, either as an injection or as an oral medication.

Age, HAE triggers, other health conditions, and your individual preferences are some factors to consider when choosing a preventive therapy.

In addition to preventive therapies, it’s important to understand and avoid triggers that can cause attacks. Anxiety, stress, injuries, illness, hormonal fluctuations (menstruation, for example), and physically demanding activities are common HAE triggers. Surgery and dental work can also trigger HAE and require special considerations for people with HAE.

Acute therapy

Acute (or “on-demand”) therapy is used to treat an attack as it happens. HAE attacks can be unpredictable, and it’s important to discuss acute therapies with your healthcare provider—you want to be ready in case an attack occurs.

Acute therapies include C1-esterase inhibitors and kallikrein inhibitors—though these are different medications than the ones used as preventive therapies. Others reduce the production of an inflammatory peptide called bradykinin (peptides are similar to proteins but smaller).

Some acute medications can be self-administered at home, while others must be given by a healthcare provider—and it’s important to consider how a medication is administered when choosing an acute therapy and when talking to a healthcare provider.

Choosing HAE therapies

Remember that HAE is a different experience for everyone. It is also a condition that changes over time—and people with HAE may require different treatments at different points in their lives.

Your healthcare provider will be your best source of information and can help you find the medications that work best for you.

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