What causes angioedema?
Angioedema is swelling that is similar to hives but occurs under the surface of the skin and in fatty tissue. It can affect many different areas of your body, including your face, throat, hands, feet, abdomen, or genitals.
Angioedema creates firm, thick welts that are often red and painful. This condition may be life-threatening if excessive swelling occurs in your throat. If you’re experiencing these symptoms and struggling to breathe, seek immediate medical attention.
Symptoms of angioedema
Swelling from angioedema can appear suddenly, often without warning. Your skin may swell in one area only or the swelling may spread throughout your body. Sometimes you’ll develop hives or welts that are painful and itchy.
Other symptoms of angioedema include:
Types of angioedema
There are five types of angioedema. Swelling can result from an allergic reaction, sensitivity to a certain medication, heredity, or an unknown substance.
This is the most common type of angioedema and occurs after eating certain foods like shellfish and peanuts. It’s also a reaction to common environmental allergens (substances that can cause an allergic reaction) like pollen and pet dander.
- Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen and naproxen
- Blood pressure medications called angiotensin-converting enzyme (ACE) inhibitor
Hereditary angioedema (HAE)
Although it is rare, this condition happens when your body can’t make enough of a specific blood protein called C1 esterase inhibitor. It causes fluid in your blood to transfer to other tissues and creates swelling. This is the most common form of angioedema and affects 85% of people who experience angioedema.
Hereditary angioedema is passed down through generations, from parents to their children. Kids often experience symptoms before the age of 12.
Another rare form, this type of angioedema occurs in adults over the age of 40. Symptoms are similar to hereditary angioedema, but acquired angioedema isn’t hereditary. It’s typically the result of a weakened immune system.
Idiopathic angioedema is angioedema that occurs without a known cause. Doctors often attribute sudden swelling that lasts more than six weeks to the following:
Causes of angioedema
Doctors believe that most angioedema cases occur when your immune system responds to a foreign invader like an allergen. This causes your body to release histamines and other chemicals into the bloodstream, creating specific symptoms. It can be difficult to pinpoint the exact cause of angioedema.
Angioedema can result from food or environmental allergens, including:
- Tree nuts or peanuts
- Pet dander
- Insect bites or stings
When to see the doctor for angioedema
Excessive swelling that comes on suddenly is a cause for concern. Call your doctor if:
- Your body isn’t responding to over-the-counter treatments like allergy medication
- You experience extreme swelling
- This is the first time you’ve experienced angioedema
Call 911 or go to the emergency room if you experience:
If you can’t breathe, that’s considered an emergency. Even minor swelling that creates breathing difficulties requires immediate medical attention.
To determine the cause of your angioedema, your doctor will ask questions about your health, symptoms, and family history. If you’ve experienced sudden swelling before, it helps to record the details of those experiences. That way, you’ll remember what happened and may be able to identify commonalities from one episode to the next.
When you visit your healthcare provider, it’s important to describe all of your symptoms and bring a list of medications you’re taking. Some prescription medications or supplements can make angioedema worse.
Physical exams, allergy skin tests, or blood tests may be necessary to help your doctor determine what is causing your angioedema.
Treatments for angioedema
The first course of treatment involves antihistamine medication to alleviate itching, reduce hives, and eliminate swelling. This won’t cure angioedema but will provide temporary relief. Sometimes, you’ll need to take several different medications or multiple doses to reduce your symptoms.
Common treatments for angioedema include:
- Over-the-counter antihistamines
- Omalizumab, an injection you’ll receive once a month
- Corticosteroids, like prednisone or prednisolone, to reduce hives in severe cases
It’s important to work with your doctor to create a treatment plan that relieves your symptoms during an outbreak. In most cases, you can reduce the amount of medication you take when you no longer continue to have symptoms.
Health Solutions From Our Sponsors
American Academy of Allergy, Asthma & Immunology: "Hives (Urticaria) and Angioedema Overview."
Columbia University Irving Medical Center: "Angioedema and Swelling Syndromes."
Mount Sinai: "Angioedema."
National Jewish Health: "Angioedema: Diagnosis."
NHS: "Causes Angioedema."
Penn Medicine: "What is Angioedema?"
UC San Diego Health: "Angioedema."
US Hereditary Angioedema Association: "Types of Angioedema."
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Food Allergies SlidesWhat common food allergens cause the most problems for adults and children? See this list of common food allergies and learn to avoid allergens with these tips.
Drug Allergy (Medication Allergy)Drug or medication allergies are caused when the immune system mistakenly creates an immune response to a medication. Symptoms of a drug allergic reaction include hives, rash, itchy skin or eyes, dizziness, nausea, diarrhea, fainting, and anxiety. The most common drugs that people are allergic to include penicillins and penicillin type drugs, sulfa drugs, insulin, and iodine. Treatment may involve antihistamines or corticosteroids. An EpiPen may be used for life-threatening anaphylactic symptoms.
Food AllergyThe most common food allergies are to eggs, nuts, milk, peanuts, fish, shellfish, strawberries and tomatoes. Symptoms and signs of a food allergy reaction include nausea, vomiting, diarrhea, abdominal pain, itching, hives, eczema, asthma, lightheadedness, and anaphylaxis. Allergy skin tests, RAST, and ELISA tests may be used to diagnose a food allergy. Though dietary avoidance may be sufficient treatment for mild allergies, the use of an Epipen may be necessary for severe food allergies.
Hereditary Angioedema (HAE)Hereditary angioedema or HAE is a genetic disease that causes swelling of the skin and tissues beneath it. Symptoms of HAE include shortness of breath, mood changes, laryngeal edema (a medical emergency), swelling of the hands and feet, muscle aches, and skin tingling. Treatment of HAE includes medication and avoidance of triggers.
Hives (Urticaria)Hives, also called urticaria, is a raised, itchy area of skin that is usually a sign of an allergic reaction. The allergy may be to food or medications, but usually the cause of the allergy (the allergen) is unknown.
How Is Angioedema Treated?Learn what medical treatments can help treat your angioedema symptoms and help you manage this condition.
Kalbitor (ecallantide) InjectionKalbitor (ecallantide) is a prescription medicine used to treat sudden attacks of hereditary angioedema (HAE) in people 12 years of age and older. Kalbitor is not a cure for HAE. It is not known if Kalbitor is safe and effective in children under 12 years of age. Serious side effects include anaphylaxis or serious allergic reactions.
Orladeyo (berotralstat)Orladeyo (berotralstat) is a prescription medicine used to prevent attacks of Hereditary Angioedema (HAE) in adults and children 12 years of age and older. Orladeyo is not used to treat an acute HAE attack. Serious side effects of Orladeyo include heart rhythm problems.