Anaphylaxis is a severe, sometimes life-threatening, allergic reaction. It affects multiple organs, including the heart and lungs.
It is important to seek emergency medical care right away if you have symptoms of anaphylaxis.
Substances that cause anaphylaxis are often called allergens or triggers. Common triggers include: Foods and food additives, especially eggs, peanuts, seafood, cow's milk, soy, fish, shellfish, seeds, and tree nutsInsect stings or bites from bees, wasps, hornets, yellow jackets, and fire antsMedications such as antibiotics (especially penicillin), medications used in anesthesia, seizure medications, and muscle relaxantsExerciseVaccinesLatex products such as gloves, medical tubing, and condomsBlood transfusions
Allergic Reaction to Medication (Hives)
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Some triggers, like dyes used in x-ray procedures, can cause a reaction similar to anaphylaxis.
Anyone can have anaphylaxis. Factors that may increase your risk of anaphylaxis include: Previous allergic reaction to an allergen, even if it is a mild reaction
Children who have
certain conditions, such as
and urogenital defects may be at increased risk for latex allergy due to heavy exposure to latex during multiple surgeries
The symptoms of anaphylaxis usually occur within minutes after exposure to an allergen, but can occur hours later. Symptoms may be mild or severe, including death. They include: Hives
Warmth or redness of skinSwelling, redness, stinging or burning, especially on the face, mouth, eyes, or handsLightheadedness and pale/blue skin colorChest tightness, shortness of breath, difficulty breathing, and wheezing
Nausea, vomiting, cramping,
, or abdominal pain
Loss of consciousness
The diagnosis of allergy with a risk of anaphylactic reactions is made based on the patient’s history. Anaphylaxis will be suspected if you have symptoms and have been exposed to a likely allergen. It is important to see a doctor who specializes in allergies (allergist/immunologist). Skin tests and sometimes blood tests can done by allergy specialists to confirm the cause of the reaction.
Anaphylaxis is a medical emergency that requires immediate medical treatment, including: Epinephrine (adrenaline) injection—makes blood vessels constrict, relaxes the airway, stops itching and hives, and relieves gastrointestinal crampingOther medications—corticosteroids and/or antihistamines may be given after the epinephrine to decrease inflammation and improve breathing.Bronchodilators—to improve breathingIV fluids—to maintain blood pressureOxygenCardiopulmonary resuscitation
(CPR)—may be necessary in severe cases when anaphylaxis leads to cardiovascular collapse. Severe anaphylaxis may require
until swelling is brought under control.
: If you receive emergency epinephrine, you should go to the emergency room right away, even if your symptoms have gone away.
Avoiding substances that trigger anaphylaxis is the best prevention. In addition: Allergy shots can decrease the risk of anaphylaxis and reduce the severity of the reactions to certain triggers.Wear a medical alert bracelet that lists your allergies.Tell your doctor or dentist about your allergies before taking any medication. When possible, ask that medications be taken as a pill. Allergic reactions can be more severe with injected medications.Your doctor may give you a self-injectable epinephrine kit to keep with you at home, work, in the car, and when you travel. Be sure family and friends know how to use the kit too.
Get training from your doctor and practice using it in the doctor's office.Make sure your epinephrine kit is not expired.Avoid any exercise that triggers a reaction. In some cases, exercise-induced anaphylaxis can be triggered by food or specific food allergies. Stop exercising at the first sign of a reaction.Make sure the school nurse and teachers know about any allergies your child has. If your child has self-injectable epinephrine, make sure school staff knows how to use it and understand when it is needed.If you are allergic to insect stings, wear protective clothing when outside.Always remain in the doctor or dentist's office 30 minutes after you have an injection. Report any symptoms right away.
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Last reviewed September 2015 by Marcin Chwistek, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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