Idiopathic angioedema is a skin reaction that causes swelling in tissues under the skin. The cause is unknown, but stress, infections, and exposure to heat or allergens may trigger it. Various treatment options are available.

Angioedema is a skin reaction that involves recurrent swelling in the tissue underneath the skin, in the upper airways, and in the gastrointestinal system. This condition usually affects the face, neck, larynx, and stomach.

There are several types of angioedema, including idiopathic angioedema. This is the most common form of the condition.

This article discusses what idiopathic angioedema is, its causes, and some of the treatments available. It also offers a few support groups that may help people form treatment plans, including lifestyle changes.

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Idiopathic angioedema is often a chronic condition. The swelling can be isolated or recurrent on a long-term basis, especially if a person also has urticaria or hives.

Doctors may diagnose chronic idiopathic angioedema when a person has three or more episodes of angioedema within a year, all of which have an unknown cause.

Some people may have idiopathic angioedema as an isolated event. Doctors will consider the condition to be acute in these cases.

Most cases of angioedema last 2–3 days before resolving.

“Idiopathic” describes a condition with an unknown cause. In other words, researchers have not yet determined what causes the inflammation and swelling.

Idiopathic angioedema is acquired, which means a person does not inherit it from their parents, nor can they pass it on to their children. Doctors classify idiopathic angioedema as histaminergic and non-histaminergic, which means it does not respond to antihistamines.

According to the National Health Service in the United Kingdom, some experts believe an unknown cause triggers the immune system, leading to idiopathic angioedema symptoms.

Other potential triggers include:

  • anxiety
  • stress
  • minor infections
  • hot or cold temperatures
  • strenuous exercise

In rare cases, a person may experience idiopathic angioedema alongside other conditions such as lupus and lymphoma.

Research into discovering potential causes and treatment of idiopathic angioedema is ongoing.

For example, researchers have evaluated whether the biologic medication omalizumab is beneficial for people with idiopathic angioedema who do and do not respond to antihistamines.

Omalizumab is a monoclonal antibody that binds to allergic antibodies called immunoglobulin E (IgE). One study suggests that 90% of people with idiopathic angioedema that did not respond to antihistamines responded well to omalizumab.

Experts are also researching the effectiveness of ecallantide, another medication that may be beneficial for people with idiopathic angioedema. People with idiopathic histaminergic angioedema appear to experience more relief from symptoms with ecallantide treatment than those with the non-histaminergic form.

Currently, there is no cure for idiopathic angioedema.

However, healthcare professionals can offer several treatments that may help ease symptoms. Additionally, some lifestyle changes to avoid triggers may reduce the severity of the condition.

Treatment of idiopathic angioedema includes medication, avoiding triggers, self-care, and dietary changes.

In addition, people may also find that home remedies, such as a cool compress, may help relieve the pain or burning sensations that accompany the swelling.

People may wish to find out what triggers their idiopathic angioedema. By knowing the triggers, a person could avoid them and potentially reduce the severity or occurrence of this condition.

However, because experts do not know the cause of idiopathic angioedema, it can be difficult to avoid triggers. People may wish to avoid medication, food, or other factors that are known triggers for other types of angioedema. A healthcare professional can also work with them to identify potential triggers.

One potential trigger of angioedema is an allergic reaction. Foods such as shellfish, medications such as antibiotics and nonsteroidal anti-inflammatory drugs (NSAIDs), and latex may increase the chance of experiencing angioedema.

Angiotensin-converting enzyme (ACE) inhibitors such as enalapril, which treats high blood pressure, may also be an angioedema trigger. Angiotensin-2 receptor blockers (ARBs), another class of medication that treats high blood pressure, are more rarely associated with angioedema.

Stress, anxiety, and hot or cold temperatures may also trigger idiopathic angioedema.

Several medications for treating idiopathic angioedema are available.

Doctors will prescribe the best medication for a person’s needs. Medications may vary depending on whether a person has histaminergic or non-histaminergic idiopathic angioedema.


Prophylactic antihistamines may be beneficial for people with idiopathic histaminergic angioedema.

Long-acting antihistamines (H-1 inhibitors) are the first line of antihistamine therapy.

Oral corticosteroids

Corticosteroids, such as prednisone, are another type of medication that can temporarily relieve swelling.

Doctors may prescribe a short treatment of steroids. People should not use steroids as a long-term treatment unless a healthcare professional recommends it.


Swelling in the airways, throat, and tongue is uncommon in idiopathic angioedema. However, it is important to be aware of this, as it can be life threatening without rapid treatment.

In this instance, doctors may inject epinephrine to rapidly reverse swelling.


Omalizumab was found effective in treating many cases of idiopathic histaminergic angioedema that are resistant to standard antihistamine therapy. Individuals should discuss this treatment with an allergist or immunologist.

Since idiopathic angioedema is unpredictable in its onset, people may wish to have a medical plan so that they and people close to them know what to do.

Some tips include:

  • Keeping medications within reach: If a person has an EpiPen, they should keep this close by. It is important to ensure the EpiPen is in date.
  • Wearing a medical alert bracelet: Medical alert bracelets can include information about triggers, medication, and emergency contacts. This may be helpful if a person is unable to communicate clearly with members of the public or emergency services.
  • Talking with friends and family: Informing friends and family of a diagnosis and treatment may help emergency services treat people more quickly. Additionally, friends and family can support a person’s treatment journey.
  • Having regular doctor appointments: People with idiopathic angioedema should have regular doctor appointments to discuss treatment options.

A chronic condition such as idiopathic angioedema can cause stress, anxiety, and worry. People may find that self-care can help reduce negative feelings and improve mental health.

For example, a person may wish to contact a therapist, either online or in-person, who specializes in chronic conditions.

People may also wish to use meditation to relieve stress.

There is currently no scientific evidence that diet can trigger or help idiopathic angioedema.

However, people with other types of angioedema may find that certain foods they are allergic to are triggers, such as:

Support groups and other organizations that create awareness around idiopathic angioedema can be helpful for people with the condition. They can help inform people about possible triggers and offer tips on treating and managing symptoms to improve their quality of life.

Social media

Support groups on social media may be helpful as people can access them from anywhere in the world.

Life Without a Fork

Life Without a Fork is a nonprofit organization that advocates for people living with idiopathic angioedema.

The organization aims to improve the quality of life of people living with the condition by raising awareness and working to change how people see and treat angioedema.


Inspire is an online community forum where people share experiences and tips for living with various medical conditions.

People can search for idiopathic angioedema on the website to read questions, answers, and general discussions about the condition. Individuals can also connect with others and post their own questions.

Living with idiopathic angioedema may be challenging, especially if someone cannot determine their triggers. However, medication such as antihistamines, omalizumab, and corticosteroids can help relieve symptoms.

Additionally, people may find that joining support groups, speaking to a therapist or counselor, and practicing self-care reduces the stress and anxiety that may result from this condition.