When the body's immune system overreacts to a substance it considers harmful, anaphylaxis occurs, a serious, potentially life-threatening allergic reaction. Different parts of the body can be affected by anaphylaxis, including the skin, respiratory system, cardiovascular system, and gastrointestinal system, which requires immediate medical attention and treatment to prevent complications and death.
Causes of anaphylaxis
Various substances can trigger anaphylaxis, which is known as an allergic reaction. The most common allergens are:
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Various foods, including peanuts, tree nuts, fish, shellfish, eggs, milk, sesame, and some fruits
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Bee stings, wasp stings, hornet stings, fire ant bites, and spider bites
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Antibiotics (especially penicillin and sulfa drugs), aspirin and other pain relievers, and contrast agents are among the medications used in some imaging procedures
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Some gloves, condoms, balloons, and medical devices contain latex, a type of rubber
Anaphylaxis can also occur due to physical exercise or without any apparent cause, called idiopathic anaphylaxis.
Symptoms of anaphylaxis
Anaphylaxis usually occurs within minutes or hours of exposure to an allergen. However, it may take several hours or even days for symptoms to appear. Symptoms of anaphylaxis may include:
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Skin reactions, such as hives, itching, flushing, swelling of the face, lips, tongue, or throat
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Respiratory symptoms, such as wheezing, coughing, shortness of breath, chest tightness, or difficulty swallowing
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Cardiovascular symptoms, such as low blood pressure, fast or irregular heartbeat, dizziness, fainting, or shock
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Gastrointestinal symptoms, such as nausea, vomiting, diarrhea, abdominal pain or cramps
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Neurological symptoms, such as headache, confusion, anxiety or panic attacks
The most dangerous symptoms of anaphylaxis are those that affect the breathing and circulation, as they can progress rapidly and become life-threatening if they are not treated immediately.
Diagnosis of anaphylaxis
The diagnosis of anaphylaxis is based on the history of exposure to a potential allergen and the presence of typical signs and symptoms. As part of a physical examination, the doctor may order a few tests to confirm the diagnosis and rule out other conditions that may cause similar symptoms.
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Skin allergy test: A small amount of the suspected allergen is applied to the skin and observed for any reaction
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Blood test: A sample of blood is taken and analyzed for the levels of certain substances that indicate an allergic response
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Serum tryptase: A blood test that measures the amount of an enzyme that is released by mast cells during an allergic reaction
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Serum histamine: A blood test that measures the amount of a chemical that is released by mast cells during an allergic reaction
Treatment of anaphylaxis
Anaphylaxis is treated by reversing the symptoms and preventing further complications. The first step is to call 911 or seek emergency medical attention. The following steps should also be followed:
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If possible, identify and remove the source of the allergen
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If available and prescribed by a doctor, use an epinephrine auto-injector (such as EpiPen) to inject a dose of adrenaline into the thigh muscle. This can help reduce the allergic response and improve breathing and blood pressure
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If breathing is difficult or stopped, perform cardiopulmonary resuscitation (CPR) until medical help arrives
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If conscious and able to swallow safely without choking or vomiting give antihistamines (such as Benadryl) to help relieve itching and hives
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If possible lie down with feet elevated above heart level to help restore normal blood flow
Hospitals or emergency departments may provide the following treatments:
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Oxygen therapy: To provide extra oxygen to the lungs and improve breathing
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Intravenous fluids: To restore fluid balance and blood pressure
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Additional doses of epinephrine: To maintain the effects of adrenaline and counteract the allergic reaction
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Corticosteroids: To reduce inflammation and swelling
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Antihistamines: To block the effects of histamine and relieve itching and hives
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Beta-agonists: To relax the muscles in the airways and ease breathing
Prevention of anaphylaxis
Anaphylaxis can be prevented by avoiding exposure to the substances that trigger it. Some strategies for preventing anaphylaxis include:
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Learn how to recognize your allergens in different situations and products
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Carry an epinephrine auto-injector and a medical alert bracelet or card that explains your allergies and how to handle anaphylaxis
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Avoid foods, medications, and personal care products that contain your allergens by reading the labels
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Tell your doctor, pharmacist, dentist, and other health care providers about your allergies and medications
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Insects may be attracted to perfumes, scented lotions, and bright colors
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Avoid walking barefoot or on grass when outdoors and wear long-sleeved clothing and shoes
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It is recommended that you seek medical advice before traveling to places where you may encounter unfamiliar allergens or have limited access to medical facilities
Anaphylaxis is a serious medical emergency that requires immediate attention and treatment. You can reduce your risk of anaphylaxis and its complications by knowing your triggers, symptoms, and treatment options. You should consult your doctor for guidance and advice if you have any questions or concerns about anaphylaxis.
