Signs and Symptoms

• Itching (often the first symptom), redness, hives, swelling, sweating
• Swelling in the nose or throat, hoarseness, wheezing, difficulty speaking, trouble breathing, chest tightness
• Abnormal heart rate or rhythm, shock, heart attack
• Stomach cramps, nausea, vomiting, diarrhea
• Dizziness, fainting

What Causes It?

Anaphylaxis occurs when your immune system overreacts to an allergen. Your body releases substances to protect you from the allergen. Instead those same substances cause your blood pressure to drop suddenly and your airways to constrict so that you have trouble breathing.

Many substances can cause anaphylaxis. Sometimes the cause isn't known. Common triggers include:

• Antibiotics (especially penicillin)
• Aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen), and prescription opiate pain medications (such as codeine)
• Foods, such as nuts, shellfish, milk, eggs, and berries
• Insect bites or stings
• Egg-based vaccines
• Latex (as in condoms, rubber gloves)
• Food coloring and preservatives (such as tartrazine, also known as FDC yellow dye No. 5)
• Exercise

Who Is Most At Risk?

Anaphylaxis is rare. The following factors may increase your risk for anaphylaxis:

• Known allergies
• Cardiovascular disease
• Substance abuse
• Asthma and other respiratory diseases
• Initial exposure to the allergen by injection (intravenous medication)
• Frequent exposure to the allergen, particularly if exposure is followed by a long delay and then a re-exposure
• Low vitamin D levels -- emerging evidence suggests low vitamin D levels may be associated with risk of anaphylaxis and food allergy.

What to Expect at Your Provider's Office

Your health care provider will perform an exam, ask about any contact you may have had with possible allergens (such as food, drugs, and insect stings), and may conduct blood or urine tests, allergy tests, or other tests.

Treatment Options

Prevention

• Avoid substances that have triggered a previous allergic response.
• If you have allergies, or suspect you do, see a specialist to be tested.
• Take medicines by mouth instead of by injection whenever possible.
• If you have a history of anaphylaxis, your doctor should coach you and your family members on how to use self-injectable epinephrine. You should carry a syringe loaded with adrenaline (epinephrine) to inject immediately after exposure to a known allergen, or at the first sign of a reaction. Also, wear a Medic Alert bracelet to alert others that you have a history of this condition. One study suggested that patients at risk of food-induced anaphylaxis carry 2 doses of epinephrine.

Treatment Plan

Get emergency medical care immediately to maintain breathing, blood pressure, and heart function, and to reverse the reaction. Your doctor may recommend oral desensitization to foods or medications to prevent future episodes.

Drug Therapies

You should receive epinephrine right away. Once at the hospital, your health care provider may give you additional drugs, including antihistamines and corticosteroids, to control symptoms and prevent delayed relapse.

Surgical and Other Procedures

For breathing trouble, health care providers may need to open the airway with an endotracheal tube and possibly connect a ventilator. Other procedures may be needed to stabilize blood pressure.

Complementary and Alternative Therapies

Anaphylaxis always requires conventional emergency medical care and should not be treated with CAM therapies. However, some CAM therapies may help lessen the severity of certain types of allergic reactions. However, some herbs and supplements -- just like prescription drugs -- can cause allergic reactions, including anaphylaxis. If you have allergies, talk to your health care provider before taking any herbs or supplements.

Nutrition and Supplements

The following nutrients may help support your immune system and reduce or prevent allergic reactions, though there is no scientific evidence they help prevent anaphylaxis. People with known triggers for anaphylaxis should avoid those triggers, even if they're using CAM therapies:

• Quercetin (400 to 500 mg per day in divided doses) -- a flavonoid and antioxidant found in many plants that may help reduce allergic reactions. Some people may get more benefit from the water-soluble form of quercetin, called quercetin chalcone. Quercetin may impact the way the liver metabolizes certain medications. If you have kidney problems, speak to your doctor before taking quercetin. If you take quercetin for more than 60 days, you should go off the supplement for 2 weeks before continuing.
• Vitamin C (1,000 mg, 2 to 6 times per day for a short period) -- Supports immune system function and enhances the effect of quercetin. Lower the dose if diarrhea develops.
• Zinc (30 mg per day) -- Animal studies suggest zinc may help protect against gastrointestinal symptoms (stomach cramps, nausea, vomiting, or diarrhea) that sometimes accompany anaphylaxis. Zinc can potentially interfere with some medications, including antibiotics and cisplatin (Platinol-AQ).

Herbs

Some herbs may help support your immune system and reduce the frequency or severity of allergic reactions, although there is no evidence they can prevent anaphylaxis. Anaphylaxis is a medical emergency. Never use herbs to treat it. Do not take herbs if you are pregnant or nursing, unless you are under the supervision of a qualified practitioner. Tell all of your health care providers about any herbal medicines you are planning to use.

• Alpinia galanga (2 to 4 g per day) -- One of several plants commonly called galangal and used as a spice in Thai food, Alpinia galanga is a member of the ginger family. Preliminary animal studies suggest it may have antihistamine properties. Take capsules or drink tea. To make tea, steep 1 g in 1 cup boiling water for 10 minutes, strain, and cool. Alpina may increase stomach acid.
• Chinese skullcap ( Scutellaria baicalensis , 1 to 2 g per day) -- May have antihistamine properties. Do not use Chinese skullcap if you are pregnant or nursing. Chinese skullcap can potentially interact with a variety of medications. Speak with your physician.
• Licorice (Glycyrrhiza glabra , 100 to 300 mg per day) -- Has been used traditionally to support the immune system and may have antihistamine properties. Licorice should only be used under the direction of a trained physician. Do not take licorice if you have high blood pressure, heart disease, kidney disease, low potassium, sexual dysfunction (in men), history of hormone-sensitive cancers, or are anticipating having surgery within 2 weeks. Licorice can interact with several medications, including warfarin (Coumadin), and others. Speak with your health care provider.
• Stinging nettle (Urtica dioica , 300 mg, 4 times per day) -- May have anti-inflammatory and antihistamine properties. Look for freeze-dried, encapsulated nettles, which are believed to retain most of the antihistamine effects of the plant. Do not use stinging nettle if you are pregnant or breastfeeding. Talk to your doctor or pharmacist if you have kidney problems or diabetes before taking stinging nettle. Stinging nettle may interact with several medications, including warfarin (Coumadin), lithium, blood pressure medications, sedative medications, and others.

Several studies suggest that medicinal plants traditionally used in Asia to prevent or treat allergic reactions may help prevent anaphylaxis. These herbal remedies include:

• Sweet chestnut tree ( Castanea crenata ) -- contains quercetin and reduced skin and blood vessels reactions related to anaphylaxis in animal studies.
• Spreading sneezeweed ( Centipeda minima ) -- contains flavonoids and is used in Traditional Chinese Medicine for its anti-inflammatory and antihistamine effects.
• Asian rose ( Rosa davurica ) -- traditionally used to support the immune system. Animal studies suggest it inhibits anaphylaxis.
• Hardy orange ( Poncirus trifoliata ) -- used traditionally for treatment of allergies. Animal studies suggest it inhibits anaphylaxis.

Researchers have tested combinations of specific herbs in animals, which show some signs of preventing anaphylaxis. You should consult a licensed, qualified herbalist for more information about these combinations.

Herbs to avoid

Although anyone can be allergic to any herbs, the following is a list of herbs that are more apt to cause allergic reactions in sensitive individuals:

• Arnica flower ( Arnica montana )
• Artichoke leaf ( Cynara scolymus ) -- in those with an allergy to artichokes
• Blessed thistle herb ( Cnicus benedictus )
• Cayenne pepper ( Capsicum spp.)
• Cinnamon bark ( Cinnamomum verum )
• Chamomile (Matricaria chamomilla)
• Dandelion root or herb ( Taraxacum officinale ) -- may trigger a reaction in those with latex allergy
• Echinacea ( Echinacea purpurea )
• Fennel oil and fennel seed ( Foeniculum vulgare )
• Feverfew ( Tanacetum parthenium/Chrysanthemum parthenium)
• Ginkgo biloba leaf extract
• Poplar bud ( Populus spp.) -- may trigger a reaction in those with salicylate (aspirin) sensitivity
• Psyllium seed ( Plantago spp.) -- allergic response more common with powder or liquid form
• St. John's wort (Hypericum perforatum)
• Yarrow ( Achillea millefolium )

Homeopathy

Anaphylaxis requires immediate emergency medical attention. While the following homeopathic remedies have been used for allergic reactions, including symptoms of anaphylaxis, they should be given only under the guidance of a certified, trained homeopath in appropriate circumstances. Anyone experiencing anaphylaxis needs emergency medical attention, not homeopahty. 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.

• Aconitum -- helps alleviate the tremendous anxiety and fear of dying that may occur during or immediately following an anaphylactic reaction
• Arnica montana -- may be used in the case of shock or following a traumatic experience
• Apis mellifica -- for puffy, rapidly-swelling skin following an insect bite or sting.

Acupuncture

Acupuncture has been used to support the immune system and to relieve symptoms of seasonal allergies, as well as to lessen chronic allergies and sensitivities. One animal study found that electroacupuncture (applying an electrical charge to acupuncture needles) helped animals survive allergic shock compared to no treatment at all. While you should never delay conventional treatment of anaphylaxis, this study suggests acupuncture may be a useful supportive therapy. More research is needed.

Prognosis/Possible Complications

Without proper treatment, anaphylaxis can be deadly. However, most people who receive proper treatment do well. Once you have anaphylaxis, you may not have it again, even with exposure to the same allergen. But the risk is high, so try to avoid substances that caused the reaction. Drugs classified as beta-blockers, monoamine oxidase inhibitors, ACE inhibitors, and ARBs may make anaphylaxis worse or interfere with treatment. If you have a history of anaphylaxis, check with your doctor or pharmacist to find out if you take one of these medications.

Following Up

You may need to stay in the hospital for 24 hours to make sure no new symptoms occur. For a severe reaction, your doctor may monitor heart function or admit you to the intensive care unit.

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