Angioedema

Related Terms

Allergic angioedema, allergies, allergic reaction, anaphylaxis, angioneurotic edema, atrophedema, Bannister disease, Bannister's disease, circumscribed edema, dysphonia, dysphagia, edema, giant hives, giant urticaria, giant wheals, hives, hymenoptera envenomations, idiopathic angioedema, Milton disease, Milton's disease, periodic edema, Quincke disease, Quincke edema, Quincke's disease, Quincke's edema, urticaria, urticaria gigans, urticaria gigantea, urticaria tuberosa, urticarial eruptions.

Background

Angioedema refers to the swelling that occurs in the tissue just below the skin. Angioedema is similar to urticaria (hives), except it occurs deeper in the skin. The swellings, known as welts, usually appear around the eyes and mouth. They may also be present on the hands, feet and throat. Angioedema can develop in anywhere from a few minutes to a few hours.
Angioedema is generally caused by an allergic reaction to either a food or medication. When an allergic reaction occurs, the immune system releases histamine and other chemicals into the bloodstream, causing allergic symptoms such as angioedema to occur. Angioedema could also be a sign of an underlying immune disorder like leukemia or Hodgkin's disease.
Angioedema that does not affect breathing is usually harmless and goes away in a few days. In most cases, angioedema does not leave any lasting marks, even without treatment. However, complications can range from dysphonia (difficulty speaking) or dysphagia (difficulty swallowing) to respiratory distress, complete airway obstruction and death.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

American Academy of Allergy Asthma & Immunology. Angioedema. .
Natural Standard: The Authority on Integrative Medicine. .
University of Maryland Medical Center. Angioedema. .

Causes

The lesions of angioedema are caused by inflammation in the skin. Allergic reactions to medications or foods can cause acute hives or angioedema.
Hives and angioedema may also occur in response to the body's production of antibodies. This might occur as the result of blood transfusions, immune system disorders (like lupus or cancer), certain thyroid disorders and infections (as serious as hepatitis or as mild as a cold).
Local trauma, like dental procedures or tonsillectomy, may trigger hereditary angioedema in the upper respiratory tract or the gastrointestinal tract.
Foods: Many foods can cause problems in sensitive people, but seafood, nuts, eggs and milk are most common.
Medications: Almost any medication may cause hives or angioedema. Antibiotics, aspirin, ibuprofen (like Advil? or Motrin?) and blood pressure medications cause allergic reactions most often.
Other allergens: Other substances that can cause angioedema include pollen, animal dander, latex and insect bites or stings.
Physical factors: Environmental factors like heat, cold, sunlight, water, pressure on the skin, emotional stress and exercise can also cause angioedema in some people.

Symptoms

Acquired angioedema (AAE):
Discolored patches of skin or rash on the hands, feet, face or genitals.
Red welts, which are itchy or painful, are usually found near the eyes, mouth, hands, feet, genitals or throat. Welts will turn pale if irritated.
Chemosis (swollen eyes) and mouth swelling.
Abdominal cramping.
Difficulty breathing.
Angioedema-eosinophilia syndrome:
Hives, itching, fever, muscle pain, decreased urination, weight gain and high leukocyte count.
Hereditary angioedema (HAE):
This type of angioedema is characterized by recurrent, self-limited attacks involving the skin, subcutaneous tissue, upper respiratory tract or gastrointestinal (GI) tract. Attacks may last from several hours to two or three days.
Sudden and severe swelling of face, arms, legs, hands, feet, genitalia, digestive tract and airway.
Swelling of digestive tract, which leads to abdominal cramping, vomiting, diarrhea, and/or reduced appetite.
Swollen airway, which causes difficulty or obstructed breathing, loss of consciousness, hoarseness or even death.
Anaphylactic shock (anaphylaxis) is a serious allergic reaction involving the heart or lungs. The bronchial tubes constrict, making it difficult to breathe. Blood pressure drops, causing dizziness and perhaps loss of consciousness or even death. Anaphylactic shock occurs suddenly and requires immediate medical care.

Treatment

Mild angioedema symptoms may not need treatment. Acute attacks usually clear up within four days with or without medication. The symptoms of mild angioedema may be reduced by not irritating the affected areas, taking cool showers, applying a cool compress, wearing loose, light clothing, minimizing vigorous activity and using over-the-counter antihistamines to help relieve the itching.
Moderate to severe symptoms may need treatment. The most common treatment for angioedema is antihistamine. Common non-prescription antihistamines include: diphenhydramine (Benadryl?), chlorpheniramine (Chlor-Trimeton?), clemastine (Tavist?) and loratadine (Alavert? or Claritin?). Antihistamines like diphenhydramine, chlorpheniramine and clemastine may cause drowsiness. Commonly used prescription medications include: desloratadine (Clarinex?), fexofenadine (Allegra?), cetirizine (Zyrtec?) and hydroxyzine (like Atarax? or Vistaril?). For severe angioedema, doctors may prescribe an oral corticosteroid drug like prednisone.
Adrenaline (Epinephrine?), terbutaline (a bronchodilator), cimetidine, corticosteroids, sedatives and tranquilizers are also used.
Serious angioedema can be life-threatening if swelling causes the throat or tongue to block the airway. Patients should seek immediate medical treatment if breathing becomes difficult. At the hospital, a tube may be inserted in the throat to keep the airway open. Nasopharyngeal intubation, endotracheal intubation or nasotracheal intubation may be performed. Also, in severe cases, steroids, H1 and H2 blockers and subcutaneous epinephrine may be administered in addition to antihistamines.
Hereditary angioedema does not respond as well to subcutaneous epinephrine, antihistamines and steroids. Stanozolol, an anabolic steroid, and danazol, a gonadotropin inhibitor, are often used to treat the acute phase of a hereditary angioedema attack. Often, patients are given aminocaproic acid for maintenance replacement of C1INH to prevent future attacks. A qualified healthcare provider should attempt to replace C1INH during the acute phase. If C1INH concentrate is unavailable, fresh frozen plasma may be used instead.

Integrative therapies

Note: In a severe angioedema attack, conventional emergency medical care should be administered immediately to open airways. Herbs or supplements should not be taken during an acute attack.
Good scientific evidence:
Bromelain: Some physicians use bromelain, an enzyme derived from pineapple, to help reduce inflammation. It is sometimes recommended to be taken with turmeric (Curcuma longa), which may enhance the effects of bromelain.
Avoid if allergic to bromelain, pineapple, honeybee, venom, latex, birch pollen, carrots, celery, fennel, cypress pollen, grass pollen, papain, rye flour, wheat flour, or members of the Bromeliaceaefamily. Use cautiously with a history of bleeding disorders, stomach ulcers, or heart, liver, or kidney disease. Use caution before dental or surgical procedures or while driving or operating machinery. Avoid if pregnant or breastfeeding.
Comfrey: Comfrey may have anti-inflammatory effects. Clinical trials investigating topical application of comfrey-containing creams have found significant reductions in inflammation and pain associated with sprains and muscle injuries. Additional study is needed to confirm these results.
Avoid if allergic/hypersensitive to comfrey, its constituents, or members of the Boraginaceae family. Avoid oral comfrey. Avoid topical comfrey on broken skin. Avoid topical comfrey in individuals with or at risk for hepatic disorders, cancer, or immune disorders. Use topical creams containing comfrey cautiously if taking anti-inflammatory medications or cytochrome P450 3A4-inducing agents. Use extreme caution when using topical creams containing comfrey for extended periods. Avoid if pregnant or breastfeeding.
Unclear or conflicting scientific evidence:
Black seed: Studies in patients with allergies found that black seed decreased allergic disease severity, slightly decreased plasma triglycerides (levels of fat within the blood), and slightly increased HDL cholesterol. The effect of black seed for allergies is still not clear and further study is required.
Avoid with a known allergy/hypersensitivity to black seed, its constituents, black seed oil, or to members of the Ranunculaceae family. Allergic contact dermatitis has been reported after topical use of black seed or the oil from the seed.
Butterbur: Preliminary research suggests that butterbur may not suppress allergic skin disease reactions when compared to the prescription drug fexofenadine (Allegra?), which does suppress these reactions. Additional study is needed.
Use caution if allergic or sensitive to Petasites hybridus or other plants from the Asteraceae/Compositae family (like ragweed, marigolds, daisies and chrysanthemums). Raw, unprocessed butterbur plant should not be eaten due to the risk of liver or kidney damage or cancer. Avoid if pregnant or breastfeeding.
Calendula: Limited early research suggests that calendula extracts may reduce skin inflammation. Human studies are lacking in this area.
Avoid if allergic to plants in the Aster/Compositae family such as ragweed, chrysanthemums, marigolds, and daisies. Use cautiously in patients taking sedatives, blood pressure medications, cholesterol medications, blood sugar-altering agents, and immunomodulators. Use cautiously with diabetes and in children. Avoid if pregnant or breastfeeding.
Cat's claw: Cat's claw may have anti-inflammatory effects, which has led to research of this herb for conditions such as rheumatoid arthritis and allergies. Large, high-quality human studies are needed comparing effects of cat's claw alone vs. placebo.
Avoid if allergic to cat's claw or Uncaria plants or plants in the Rubiaceae family such as gardenia, coffee, or quinine. Avoid with a history of conditions affecting the immune system (such as AIDS, HIV, some types of cancer, multiple sclerosis, tuberculosis, rheumatoid arthritis, lupus). Use cautiously with bleeding disorders or a history of stroke, or if taking drugs that may increase the risk of bleeding. Discontinue use two weeks before surgery/dental/diagnostic procedures with bleeding risk, and do not use immediately after these procedures. Cat's claw may be contaminated with other Uncaria species. Reports exist of a potentially toxic, Texan grown plant, Acacia gregii being substituted for cat's claw. Avoid if pregnant, breastfeeding, or trying to become pregnant.
Dandelion: Research in laboratory animals suggests that dandelion root may possess anti-inflammatory properties. There is a lack of well-conducted human studies currently available in this area.
Avoid if allergic to chamomile, feverfew, honey, yarrow, or any related plants such as aster, daisies, sunflower, chrysanthemum, mugwort, ragweed, or ragwort. Use cautiously with diabetes or bleeding disorders, gastroesophageal reflux disease (GERD), kidney or liver diseases, or a history of stroke or electrolyte disorders. Potassium blood levels should be monitored. Stop use two weeks before surgery/dental/diagnostic procedures with bleeding risk and do not use immediately after these procedures. Avoid if pregnant or breastfeeding.
Euphorbia: Euphorbia balsamifera has been studied in patients with acute dental pulpitis, and may be comparable to that of pulpal nerve caustics. Additional study is necessary to make a recommendation for oral inflammation.
Avoid if allergic or hypersensitive to pollen from Euphorbia fulgens. Use cautiously with history of Epstein Barr virus infection or stomach conditions. Avoid if pregnant or breastfeeding.
Eyebright: Several iridoid glycosides isolated from eyebright, particularly aucubin, may possess anti-inflammatory properties comparable to those of indomethacin (a nonsteroidal anti-inflammatory drug). However, there is currently insufficient evidence to recommend for or against eyebright as an anti-inflammatory agent.
Avoid with a known allergy or hypersensitivity to eyebright. Hypersensitivity to members of the Scrophulariaceae family may lead to a cross-sensitivity reaction. Use cautiously as an eye treatment, particularly homemade preparations, due to the risk of infection if not sterile. Use cautiously with diabetes and drugs that are broken down by the liver. Avoid if pregnant or breastfeeding.
Hypnotherapy, hypnosis: It has been suggested that hypnotherapy may be effective for allergies. However, further research is necessary to determine whether it is an effective treatment.
Use cautiously with mental illnesses like psychosis/schizophrenia, manic depression, multiple personality disorder or dissociative disorders. Use cautiously with seizure disorders.
Jewelweed: Jewelweed has been used traditionally as a treatment for various types of contact dermatitis, including poison ivy/oak rashes and allergic dermatitis, however, human study indicates that it may not be effective for this use.
Avoid if allergic or hypersensitive to jewelweed (Impatiens biflora), its constituents, or members of the Balsaminaceae family. Use cautiously if taking calcium supplements and with kidney stone disorders. Avoid consuming excess amounts of jewelweed due to reports of high mineral content, particularly calcium oxalate. Avoid if pregnant or breastfeeding.
Lactobacillus acidophilus: Limited available study suggests that the Lactobacillus acidophilus (L. acidophilus) strain L-92 (L-92) may be effective for the treatment of Japanese cedar-pollen allergy. Further research is needed to confirm these results.
L. acidophilus may be difficult to tolerate if allergic to dairy products containing L. acidophilus. Avoid with history of an injury or illness of the intestinal wall, immune-disease, or heart valve surgery. Avoid with prescription drugs, such as corticosteroids, because of the risk of infection. Use cautiously with heart murmurs. Antibiotics or alcohol may destroy L. acidophilus. Therefore, it is recommended that L. acidophilus be taken three hours after taking antibiotics or drinking alcohol. Some individuals may use antacids, such as famotidine (Pepcid?) and esomeprazole (Nexium?), to decrease the amount of acid in the stomach one hour before taking L. acidophilus.
Licorice: Many medical conditions are marked by inflammation. Because licorice can affect the metabolism of steroids, licorice is sometimes used to help decrease inflammation. Additional study is needed to make a conclusion.
Avoid with a known allergy to licorice, any component of licorice, or any member of the Fabaceae (Leguminosae) plant family. Avoid with congestive heart failure, coronary heart disease, kidney or liver disease, fluid retention, high blood pressure, hormonal abnormalities or if taking diuretics. Licorice can cause abnormally low testosterone levels in men or high prolactin or estrogen levels in women. This may make it difficult to become pregnant and may cause menstrual abnormalities.
Marshmallow: Marshmallow extracts have traditionally been used to treat inflammatory skin conditions. Several laboratory experiments, mostly in the 1960s, reported marshmallow to have anti-inflammatory activity but limited human study is available. Safety, dosing, and effectiveness compared to other anti-inflammatory agents have not been examined.
Historically, marshmallow is generally regarded as being safe in healthy individuals. However, since studies have not evaluated the safety of marshmallow, proper doses and duration in humans are not known. Allergic reactions may occur. There is not enough scientific evidence to support the safe use of marshmallow during pregnancy or breastfeeding.
Onion: Early research shows that topical application of an alcoholic onion extract significantly reduced responses to allergies, such as wheals (hives) and flares. More research is needed.
Avoid if allergic or hypersensitive to onion (Allium cepa), its constituents, or members of the Lilaceae family. Use cautiously with hematologic (blood) disorders, diabetes, hypoglycemia (low blood sugar), and hypotension (low blood pressure). Use cautiously if taking anticoagulants or antiplatelets (blood thinners). Avoid medicinal doses if pregnant or breastfeeding.
Para-aminobenzoic acid: Para-aminomethylbenzoic acid (PABA) may be useful in the treatment of lichen slerosus, a benign, progressive dermatologic condition characterized by inflammation, pruritus (itching), and pain, especially in the anogenital region (involving the anus and genitals). Additional investigations are needed regarding the use of PABA for inflammatory skin disorders.
Avoid with known hypersensitivity to PABA or its derivatives. Discontinue use if rash, nausea, or anorexia occurs. Avoid oral use in children and pregnant or nursing women. Use cautiously in patients with renal or liver disease. PABA should not be given concurrently with sulfonamides. Use cautiously in patients with bleeding disorders or taking anticoagulants. Use cautiously in patients with diabetes or hypoglycemia.
Peony: Peony root may have beneficial effects on immune function. These effects may help decrease inflammation associated with allergic skin reactions such as allergic dermatitis. There is currently not enough evidence to recommend for or against the use of peony in allergic skin conditions.
Avoid if allergic or sensitive to peony. Avoid with bleeding disorders or if taking drugs, herbs, or supplements that increase bleeding risk. Use cautiously with estrogen-sensitive cancers or if taking drugs, herbs, or supplements with hormonal activity. Avoid if pregnant or breastfeeding.
Perilla: Preliminary evidence suggests some benefit of perilla extract for seasonal allergies. Further clinical trials are required before conclusions can be made.
Avoid if allergic/hypersensitive to perilla or members of the Lamiaciae/Labiatae family. Use cautiously with cancer, low HDL-cholesterol, and immune disorders. Use cautiously if taking NSAIDS or barbiturates. Avoid if pregnant or breastfeeding.
Probiotics: Only a few types and combinations of probiotics have been studied as a possible allergy treatment. They have been studied mostly in children, teenagers, and young adults. Further research is necessary before a firm conclusion can be made. Probiotics are generally considered safe and well tolerated. Avoid if allergic or hypersensitive to probiotics. Use cautiously if lactose intolerant.
Stinging nettle: Limited available clinical study has examined the effectiveness of a topical combination product containing stinging nettle for insect bites. Results did not show a significant reduction in erythema or itching with the nettle-containing cream. Further well-designed clinical trials are required before a firm conclusion can be made.
Avoid if allergic or hypersensitive to nettle, the Urticaceae family, or any ingredient of nettle products. Use cautiously with diabetes, bleeding disorders, and/or low sodium levels in the blood. Use cautiously with diuretics and anti-inflammatories. The elderly should also use nettle cautiously because nettle may drastically reduce blood pressure. Avoid if pregnant because in one animal study, nettle caused uterine contractions. Avoid if breastfeeding due to insufficient evidence of safety.
Tea tree oil: Small studies show that tea tree oil applied to the skin may reduce allergic skin reactions caused by histamine-induced inflammation. Further research is needed to confirm these results.
Avoid allergic or hypersensitive to tea tree oil (Melaleuca alternifolia), any of its constituents, balsam of Peru, benzoin, colophony (rosin) tinctures, eucalyptol, or members of the Myrtle (Myrtaceae) family. Avoid taking tea tree oil by mouth. Avoid if taking antineoplastic agents. Use tea tree oil applied to the skin cautiously in patients with previous tea tree oil use. Avoid if pregnant or breastfeeding.
Thyme: Historically, thyme has been used topically for a number of inflammatory skin disorders. Results are mixed. Additional study is needed in this area.
Avoid with known allergy/hypersensitivity to members of the Lamiaceae (mint) family or to any component of thyme, or to rosemary (Rosmarinus officinalis). Avoid oral ingestion or non-diluted topical application of thyme oil due to potential toxicity. Avoid topical preparations in areas of skin breakdown or injury, or in atopic patients, due to multiple reports of contact dermatitis. Use cautiously in patients with gastrointestinal irritation or peptic ulcer disease due to anecdotal reports of gastrointestinal irritation. Use cautiously in patients with thyroid disorders due to observed anti-thyrotropic effects in animal research of the related species Thymus serpyllum. Avoid if pregnant or breastfeeding.
Thymus extract: Thymus extract may reduce allergy symptoms due to its potential immune stimulating effects. More clinical trials are required before recommendations can be made involving thymus extract for this use.
Avoid if allergic or hypersensitive to thymus extracts. Use bovine thymus extract supplements cautiously due to potential for exposure to the virus that causes "mad cow disease." Avoid use with an organ transplant or other forms of allografts or xenografts. Avoid if receiving immunosuppressive therapy, with thymic tumors, myasthenia gravis (neuromuscular disorder), untreated hypothyroidism, or if taking hormonal therapy. Avoid if pregnant or breastfeeding; thymic extract increases human sperm motility and progression.
Turmeric: Turmeric is a perennial plant native to India and Indonesia, and it is often used as a spice in cooking. Laboratory and animal studies show activity against inflammation for turmeric and its constituent curcumin. Reliable human research is lacking.
Avoid if allergic or hypersensitive to turmeric (curcumin), yellow food colorings or plants belonging to the Curcuma or Zingiberaceae (ginger) families. Use cautiously with history of bleeding disorders, immune system deficiencies, liver disease or gallstones. Use cautiously with blood-thinners (e.g. warfarin). Use cautiously if pregnant or breastfeeding.
Witch hazel: A homeopathic formulation containing an extract of witch hazel and tinctures of other botanicals was studied for its effects in relieving redness and itching associated with mosquito bites. According to study results, the formulation did not provide effective relief from mosquito bite symptoms. However, because information about the strength or concentration of the witch hazel extract used was not available, and witch hazel was not evaluated alone, conclusions about the effects of witch hazel on symptoms of insect bites cannot be made. Additional research is needed in this area.
Avoid if allergic or sensitive to witch hazel. Avoid if pregnant or breastfeeding. Use cautiously in people with liver or kidney disorders, diabetes, and in children.
Fair negative scientific evidence:
Papain: A comparative controlled trial did not find a clinically or statistically significant difference between fire ant bites treated with papain or placebo.
Use cautiously in patients with bleeding disorders or taking anticoagulants or antiplatelets. Use cautiously with radiation therapy or in patients being treated for prostatitis. Avoid in patients with gastroesophageal reflux disease or in patients using immunosuppressive therapy. Avoid in patients allergic or sensitive to papain.
Traditional or theoretical uses lacking sufficient evidence:
Acupuncture: Some clinicians claim that acupuncture may help boost the immune system and lessen the frequency or severity of allergic responses like angioedema. However, more scientific research is needed before any recommendations can be made for allergies.
Needles must be sterile in order to avoid disease transmission. Avoid with valvular heart disease, infections, bleeding disorders, medical conditions of unknown origin, or neurological disorders. Avoid if taking drugs that increase the risk of bleeding (e.g. anticoagulants). Avoid on areas that have received radiation therapy and during pregnancy. Use cautiously with pulmonary disease (e.g. asthma or emphysema). Use cautiously in elderly or medically compromised patients, diabetics, or with history of seizures. Avoid electroacupuncture with arrhythmia (irregular heartbeat) or in patients with pacemakers because therapy may interfere with the device.
Apple cider vinegar: Apple cider vinegar has been used traditionally as a topical treatment for insect stings, including bee stings. Scientific evidence supporting the use of apple cider vinegar for insect bites is currently lacking.
Apple cider vinegar is likely safe when taken by mouth as food flavoring. Use caution if allergic or hypersensitive to apple cider vinegar or any of its ingredients (like apples and pectin). Use caution with a history of low potassium levels, diabetes or osteoporosis. Avoid if pregnant or breastfeeding.
Chamomile: Based on anecdotal evidence, dried chamomile flowers have been added to bath water as a topical treatment for insect bites. Currently, human trials have not evaluated the safety or effectiveness of chamomile for these uses.
Avoid if allergic to chamomile or any related plants, such as aster, chrysanthemum, mugwort, ragweed, or ragwort. Stop use two weeks before and immediately after surgery/dental/diagnostic procedures with bleeding risks. Use cautiously if driving or operating machinery. Avoid if pregnant or breastfeeding.
Devil's claw root: Devil's claw root may help reduce inflammation and skin lesions. Additional research is needed regarding anti-inflammatory effects.
Avoid if allergic to devil's claw or to plants in the Harpagophytum procumbens family. Use caution with stomach ulcers or history of bleeding disorders, diabetes, gallstones, gout, heart disease, stroke, ulcers, or with prescription drugs used for these conditions. Stop use two weeks before surgery/dental/diagnostic procedures with bleeding risk, and do not use immediately after these procedures. Avoid if pregnant or breastfeeding.
Ginkgo biloba: Ginkgo biloba extract has been used for allergies and inflammation. However, in rare cases, Ginkgo has been reported to cause an allergic reaction on the skin.
Avoid if allergic or hypersensitive to members of the Ginkgoaceaefamily. If allergic to mango rind, sumac, poison ivy or oak or cashews, then allergy to ginkgo is possible. Avoid with blood-thinners (like aspirin or warfarin (Coumadin?)). Ginkgo seeds are dangerous and should be avoided. Skin irritation and itching may also occur due to ginkgo allergies. Do not use ginkgo in supplemental doses if pregnant or breastfeeding.
Goldenseal: Goldenseal (Hydrastis canadensis) has been used as an antihistamine and to treat severe symptoms of allergies like stomach pain, diarrhea, and decreased appetite.
Avoid if allergic or hypersensitive to goldenseal or any of its constituents, like berberine and hydrastine. Use cautiously with bleeding disorders, diabetes, or low blood sugar. Avoid if pregnant or breastfeeding.
Quercetin: Quercetin, a naturally occurring flavonoid, may reduce the likelihood of a reaction to allergies. The recommended amount is generally 200 to 400 miligrams three times daily before meals, according to a review by the University of Maryland Medical Center. Avoid citrus-based forms of flavonoids if sensitive to citrus or if taking calcium-channel blockers to treat high blood pressure.
Quercetin is generally considered safe when taken at doses normally found in foods. Avoid if allergic or hypersensitive to quercetin. Possible eye, skin, gastrointestinal and/or respiratory tract infection may occur. Avoid if pregnant or breastfeeding.

Prevention

To prevent recurrent angioedema, avoid irritating the affected area, stay away from known allergens and avoid extreme temperatures.
Allergy testing with a trained specialist may help identify potential triggers. Certain foods and food additives may trigger angioedema in susceptible people. Common food triggers include: seafood, nuts, legumes, eggs, chocolate, milk and berries.
Individuals who are prone to angioedema should wear a Medic Alert bracelet that notes their condition.
Patients should never take medications that are not prescribed for them.
Individuals who have a disorder associated with hives and angioedema, such as lupus, lymphoma or thyroid disease, are more susceptible to develop angioedema. Individuals should tell their doctor if they have a family history of hives, angioedema or hereditary angioedema.

Types of angioedema

Hereditary angioedema (HAE) is genetic and tends to recur. This inherited form of angioedema is related to low levels or abnormal functioning of certain blood proteins (C1 inhibitors). These inhibitors help regulate immune system functions.
Acquired angioedema (AAE) is not genetic. It is characterized by painless, non-pitting, non-pruritic swelling of the skin. This form of angioedema occurs as a reaction to histamine or other chemicals in the blood. This form of angioedema is often, although not always, the result of an allergic reaction.
Angioedema-eosinophilia syndrome causes a fever, hives or itchiness. This form of angioedema is characterized by a high leukocyte count, muscle pain, weight gain or decreased urination.

Angioedema and urticaria

Angioedema and urticaria are different manifestations of the same pathologic process. In both conditions, postcapillary venule inflammation results in fluid leakage and edema (swelling). However, angioedema involves vessels in the layers of the skin below the dermis, while urticaria is localized to the superficial portion of the dermis.
The subdermal source of angioedema results in well-demarcated, localized, non-pitting edema. Urticaria is characterized by well-circumscribed wheals with raised erythematous borders and central blanching.
Angioedema and urticaria can occur together or separately. Recurrent episodes of one or both conditions for less than a six-week period are considered acute, whereas longer-lasting outbreaks are considered chronic.