Angioedema refers to swelling that happens just below the surface of the skin, most often around the lips and eyes. In an allergic reaction, the body produces histamine, which causes blood vessels to swell. Angioedema is similar to hives, but with hives there are itchy red welts on the surface of your skin. Angioedema is a deeper swelling. Both hives and angioedema are usually caused by an allergic reaction, to either a food or medication. Things like pollen or insect stings can also cause angioedema. In rare cases, it may be a sign of an underlying condition such as leukemia or Hodgkin's disease. There are two basic types of angioedema:

• Hereditary angioedema (HAE), a rare condition that is genetic
• Acquired angioedema (AAE)

Angioedema can take anywhere from minutes to hours to develop. It may affect an area on one side of the body but not on the other. In most cases, angioedema is mild. Severe angioedema can cause the throat or tongue to swell, cutting off the airway, and it can be life threatening.

Common symptoms of angioedema include:

• Sudden appearance of red welts, especially near the eyes and lips, but also on the hands, feet, and the inside of the throat
• Burning, painful, swollen areas; sometimes itchy
• Discolored patches or rash on the hands, feet, face, or genitals
• More rarely, hoarseness, tight or swollen throat, breathing trouble
• In a form called angioedema-eosinophilia syndrome, hives, itching, fever, muscle pain, decreased urine, weight gain, and high white blood cell count occur.

Sometimes the cause is unknown. An angioedema reaction may be caused by allergies to foods, dyes, or pollen, or certain medications. Foods that often cause allergies include shellfish, dairy, and nuts. Drugs that often spark allergic reactions include nonsteroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen or Advil), blood pressure medications, aspirin, and antibiotics. Conditions such as leukemia, Hodgkin's disease, and connective tissue disorders (such as lupus) may also trigger angioedema.

These factors increase the risk for angioedema:

• Having hives or angioedema before
• Having had a body-wide allergic reaction in the past
• Experiencing injury, sudden temperature change, stress, or anxiety
• Undergoing a dental procedure
• Having ovarian cysts

Your health care provider will do a physical exam and ask about your symptoms. Be sure to tell your health care provider about all medications (prescription and over-the-counter), herbs, and supplements you are taking. Blood and urine tests may help pinpoint the cause of the angioedema.

Prevention

You should eliminate any known or suspected triggers for allergies. Allergy testing with a trained specialist may help identify allergens. If you are prone to angioedema, you should wear a Medic Alert bracelet.

Treatment Plan

If you have mild angioedema, you may be able to treat it with over-the-counter antihistamines or alternative therapies. With severe angioedema, the first priority is to ensure that the person’s airway is open and they can breathe. The next steps include identifying and removing the allergen as well as relieving other symptoms. You can manage infrequent attacks as they happen. Frequent attacks may require ongoing treatment, perhaps with an allergist, dermatologist, or other specialist.

Drug Therapies

Several medicines may help prevent or relieve attacks. For mild cases, you can use over-the-counter antihistamines, such as Benadryl, Zyrtec, or Claritin. Note that Benadryl often causes drowsiness.

Your doctor may prescribe antihistamines. Mild attacks tend to clear up within 4 days with or without medication. Common antihistamines include fexofenadine (Allegra), cetirizine (Zyrtec), and desloratadine (Clarinex). For severe cases, your doctor may prescribe corticosteroids to reduce swelling and itching, or you may need a shot of epinephrine (EpiPen).

Complementary and Alternative Therapies

In a severe attack, you should seek emergency care immediately. Do not take any new drugs, herbs, or supplements during an attack.

Following a good nutritional plan and using some herbs in between attacks may help reduce or prevent angioedema. Herbs and supplements may help reduce mild symptoms, particularly for chronic and recurring forms. It is important to tell your doctor about all medications, herbs, and supplements you are taking.

Nutrition and Supplements

Some foods may trigger angioedema in people who are allergic. You should eliminate any foods or food additives that trigger symptoms. The following are the most common food triggers:

• Seafood
• Nuts
• Legumes
• Eggs
• Chocolate
• Milk
• Berries

Some people may have a reaction in response to:

• Citrus fruits
• Sulfites -- used as an antioxidant or freshening agent (preservative) in many foods and beverages
• Yellow dye No. 5 (also called tartrazine) -- those who are allergic to aspirin or other NSAIDs are more susceptible to having an allergy to yellow dye No. 5

Health care providers can help identify food triggers by:

• Getting detailed information about your diet
• Doing skin tests for sensitivity to certain substances
• Testing suspected triggers
• Monitoring symptoms as foods are eliminated from your diet, then slowly re-introduced one at a time

If you have gastrointestinal symptoms (abdominal pain, vomiting, diarrhea, or reduced appetite), you may want to try a diet that eliminates common food triggers even if you do not have a specific food allergy.

These supplements may also help treat symptoms:

• Vitamin C (2 - 4 g per day) may help lower histamine levels. Reduce dose if diarrhea develops.
• Vitamin B12 (1,000 mcg per week by injection) may help reduce the frequency of chronic attacks. It is not known whether taking oral B12 would have the same effect.
• Quercetin (a plant-based flavonoid) may reduce the likelihood of an allergic reaction. The recommended amount is generally 200 - 400 mg three times a day before meals. If you are sensitive to citrus or take calcium-channel blockers to treat high blood pressure, you should avoid citrus-based forms of flavonoids. Quercetin is best absorbed in its water-soluble form, often referred to as hesperidin methyl chalcone (HMC). Few manufacturers make this form, so it can be harder to find. Talk to your doctor about which form of quercetin is best for you.
• Bromelain is sometimes used to help reduce inflammation. You can take it with curcumin (Curcuma longa), the yellow pigment of turmeric, which may make its effects stronger. Avoid bromelain if you are allergic to citrus. Bromelain may increase the risk of bleeding, so ask your doctor before taking bromelian if you take blood-thinning medication such as aspirin or warfarin (Coumadin).

Herbs

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and can interact with other herbs, supplements, or medications. For these reasons, take herbs with care, under the supervision of a health care provider.

You may use herbs as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, you should make teas with 1 tsp. herb per cup of hot water. Steep covered 5 - 10 minutes for leaf or flowers, and 10 - 20 minutes for roots. Drink 2 - 4 cups per day. You may use tinctures alone or in combination as noted.

• Green tea may have antihistamine properties. Drink three cups per day. If caffeine is a problem for you, drink decaffeinated tea.
• Devil's claw (Harpagophytum procumbens, 2 - 2.5 g per day) may reduce inflammation and skin lesions. Do not take devil's claw if you take blood pressure medication or blood-thinning medication, or if you have diabetes.
• Goldenseal (Hydrastis canadensis, 250 - 500 mg three times per day) has been used for gastrointestinal symptoms such as stomach pain, diarrhea, and reduced appetite that may go along with a severe allergic reaction. Some health care providers also recommend goldenseal for those with food allergies to prevent or reduce allergic reactions.
• Licorice root (Glycyrrhiza glabra, 200 - 400 mg 3 times per day) has been used traditionally to reduce inflammation in the case of an allergic reaction. It may also help support immune system health. Do not take licorice if you have heart disease, high blood pressure, or edema, or if you take warfarin (Coumadin) or diuretics (water pills).
• Chamomile (Matricaria recutita) has been used traditionally to treat hives, although there is no scientific evidence that it works. To make a tea, steep 2 - 4 g of fresh flower heads in a cup of boiling water for 10 minutes. Strain and cool. Drink 3 times per day. Ask your doctor before taking chamomile if you take warfarin (Coumadin).

Homeopathy

Before prescribing a remedy, homeopaths take into account a person's constitutional type -- your physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.

• Apis is traditionally used for hives and angioedema and may be useful to prevent or treat chronic, recurrent cases.

Acupuncture

Some doctors report that acupuncture may help reduce the frequency or severity of allergic reactions such as angioedema.

If angioedema affects the throat, the person’s airway could be blocked, which could be life-threatening. In rare cases, angioedema may develop into anaphylaxis, which requires emergency medical care to maintain breathing, blood pressure, and heart function and to reverse the reaction.

After an attack, it's important to identify and avoid any triggers and to treat any underlying condition.

Blumenthal M, Goldberg A, Brinckmann J, eds. Herbal Medicine: Expanded Commission E Monographs. Newton, Mass: Integrative Medicine Communications; 2000:84-87, 160-169, 233-239.

Chinen J, Shearer WT. Advances in basic and clinical immunology in 2006. J Allergy Clin Immunol. 2007 Aug;120(2):263-70.

Cicardi M, Bergamaschini L, Cugno M, et al. Pathogenic and clinical aspects of C1 inhibitor deficiency. Immunobiol. 1998;199(2):366-376.

Johnston S, Martin LJ, Cai X. Antihistamine effect of supplemental ascorbic acid and neutrophil chemotaxis. J Am Coll Nutr. 1992;11:172-6.

Kumar SA, Martin BL. Urticaria and angioedema: diagnostic and treatment considerations. J Am Osteopath Assoc. 1999;99(3 suppl):S1-S4.

Matsuo N, Yamada K, Shoji K, et al. Effect of tea polyphenols on histamine release from rat basophilic leukemia (RBL-2H3) cells: the structure-inhibitory activity relationship. Allergy. 1997;52:58-64.

Paganelli R, Fagiolo U, Cancian M, Scala E. Intestinal permeability in patients with chronic urticaria-angioedema with and without arthralgia. Ann Allergy. 1991;66(2):181-184.

Pizzorno JE Jr, Murray MT. Textbook of Natural Medicine. Vol. 1. 2nd ed. New York, NY: Churchill Livingstone; 1999:619-623, 746-749, 751-759.

Shah UK, Jacobs IN. Pediatric angioedema: ten years' experience. Arch Otolaryngol Head Neck Surg. 1999;125(7):791-795.

Waytes AT, Rosen FS, Frank MM. Treatment of hereditary angioedema with a vapor-heated C1 inhibitor concentrate. N Engl J Med. 1996;334(25):1630-1634.

Zuraw BL. Novel therapies for hereditary angioedema. Immunol Allergy Clin North Am. 2006 Nov;26(4):691-708.

Zuraw BL. Urticaria, angioedema, and autoimmunity. Clin Lab Med. 1997;17(3):559-569.