Anaphylaxis is a severe allergic reaction that can be fatal for many. It occurs rapidly and requires immediate medical attention. Allergies are common, but anaphylaxis is a rare, extreme reaction that affects multiple body systems at once. According to the Centers for Disease Control and Prevention (CDC), anaphylaxis affects approximately 1 in 50 Americans, though some experts believe the actual number may be higher due to underreporting.
The condition can develop within seconds or minutes of exposure to an allergen, such as certain foods, medications, insect stings, or latex. Anaphylactic shock occurs when the body’s immune response causes a dangerous drop in blood pressure. This leads to the loss of consciousness or death if not treated promptly. Keep reading to learn more about anaphylaxis, its causes, key symptoms, methods of diagnosis, and effective treatment options.
What Is Anaphylaxis?
Anaphylaxis is an extreme allergic reaction that can occur within seconds to minutes, though delayed reactions may also develop over an hour. It affects the respiratory, cardiovascular, digestive, and skin systems. When exposed to an allergen, the immune system releases immunoglobulin E (IgE) antibodies. These antibodies trigger mast cells and basophils, which release histamines and other inflammatory mediators into the bloodstream. This cascade of events leads to widespread inflammation, increased vascular permeability, and constriction of airways.
In severe cases, blood pressure drops dangerously low, a condition known as a shock drop. In this situation, airways narrow down, and extreme swelling occurs due to allergic reactions. Symptoms can appear within minutes of exposure to an allergen, although they may also take longer, developing over an hour. Thus, knowing the rapid onset of anaphylaxis symptoms is important for fast action.
Common Anaphylaxis Triggers You Need to Know
Various allergens can trigger anaphylaxis. Therefore, people should be aware of allergens that they may be sensitive to and can cause severe reactions. Moreover, they should avoid these triggers to prevent future reactions. Some of the common allergens are discussed as follows:
- Food Allergens
Foods are the most common cause of anaphylaxis, particularly in children. Common food triggers include peanuts, tree nuts (e.g., almonds, walnuts), shellfish (e.g., shrimp, crab), fish, milk, eggs, and wheat. Even trace amounts can provoke an anaphylactic reaction in susceptible individuals.
For those with known food allergies, strict avoidance and carrying an epinephrine auto-injector are necessary preventive measures. An epinephrine auto-injector is a portable device that delivers a precise dose of epinephrine (adrenaline) to counteract severe allergic reactions. In case of accidental exposure, injecting epinephrine relaxes airway muscles, reduces swelling, stabilizes blood pressure, and provides critical time to seek medical assistance.
- Medications
Medications, especially antibiotics containing penicillin and cephalosporins (both β-lactam antibiotics), are common triggers of anaphylactic shock. Nonsteroidal anti-inflammatory drugs (NSAIDs), like aspirin and ibuprofen, which contain compounds that inhibit cyclooxygenase (COX) enzymes, can also lead to severe allergic reactions.
Additionally, certain vaccines that include adjuvants or preservatives may trigger anaphylaxis in sensitive individuals. Anaphylaxis can occur even if the medication was previously tolerated without issues.
- Insect Stings
Hymenoptera stings from bees, wasps, hornets, and fire ants are known to cause severe allergic reactions. The venom in these insect stings can trigger anaphylaxis in allergic individuals, as the body releases histamines and other chemicals in response. After an initial sting, a person may become sensitized, which increases the risk of a more severe reaction upon subsequent stings.
- Latex
Latex, a natural rubber found in many medical supplies and everyday items, can also cause anaphylaxis. Healthcare workers, individuals with frequent surgeries, or people with certain food allergies (such as bananas or avocados) are at a higher risk of developing a latex allergy. The most dangerous reactions occur with direct exposure to latex in surgical gloves or catheters.
- Exercise-Induced Anaphylaxis
A rare but recognized cause of anaphylactic reactions is exercise-induced anaphylaxis, which occurs after physical exertion. This condition can be further complicated if exercise is combined with specific food intake or temperature changes.
Individuals with this form of anaphylaxis may experience symptoms after vigorous activity, and the condition can be managed by avoiding exercise shortly after eating.
Read More: How to Identify Common Causes of Rashes in Adults
How to Identify Anaphylaxis Symptoms Before It’s Too Late?
Anaphylaxis symptoms can appear within minutes or even take hours. Therefore, people dealing with an emergency must understand how these anaphylaxis symptoms appear and what complications can arise for fast action:
- Respiratory Symptoms
The most serious symptoms of anaphylaxis involve the respiratory system. These include difficulty breathing, shortness of breath, wheezing, and chest tightness. The airway may become blocked due to swelling of the tongue or throat, leading to stridor (a high-pitched, wheezing sound). In severe cases, airway obstruction can be fatal without rapid intervention.
- Skin Reactions
Anaphylactic reactions often involve noticeable skin changes. Hives (urticaria), flushing, and intense itching (pruritus) are common skin reactions. Hives are raised with red patches on the skin that are often itchy and vary in size.
Swelling (angioedema) may also occur, especially around the eyes, lips, hands, and feet. As swelling becomes severe, a person may develop a shocked face.
- Cardiovascular Symptoms
Cardiovascular symptoms are critical signs of anaphylactic shock. These include a rapid heartbeat (tachycardia), a weak pulse, and a sudden shock drop in blood pressure (hypotension). This drop in blood pressure can cause dizziness, lightheadedness, or fainting. In severe cases, blood pressure can plummet to dangerous levels, which can lead to collapse and loss of consciousness.
- Gastrointestinal Symptoms
The gastrointestinal system may also be affected, with symptoms such as nausea, vomiting, abdominal cramps, and diarrhea. These symptoms often occur alongside other signs of anaphylaxis and may be mistaken for food poisoning if not recognized promptly.
- Neurological Symptoms
As blood pressure drops and oxygen levels decrease, neurological symptoms such as confusion, agitation, or even loss of consciousness may occur. Headaches and blurred vision are also possible. These symptoms indicate the brain is not receiving enough oxygen, which requires immediate medical intervention.
How is Anaphylaxis Diagnosed?
Anaphylaxis is diagnosed mainly by observing symptoms. Its sudden onset and involvement of multiple body systems make it a medical emergency that needs quick action. If you have an anaphylactic reaction, here’s what you can expect:
- Clinical Examination
The doctor begins with a medical history of allergic reactions and assesses the patient’s symptoms, including hives, swelling, breathing difficulties, and low blood pressure. The sudden appearance of these symptoms after exposure to a known allergen is often enough to diagnose anaphylaxis. The medical team will quickly assess the severity of the reaction to determine the appropriate treatment.
- Skin Prick Tests
To identify specific allergens responsible for anaphylaxis, allergy specialists may perform a skin prick test. During this test, small amounts of potential allergens are introduced to the skin through tiny pricks, and any reaction (such as redness or swelling) is monitored. This helps pinpoint the allergen responsible for the reaction.
- Blood Tests
In some cases, a blood test for serum tryptase levels is conducted. Tryptase is an enzyme released by mast cells during an allergic reaction. Elevated levels of tryptase in the blood within a few hours of an allergic event confirm the diagnosis of anaphylaxis. Blood tests are often used after the acute phase to support the diagnosis.
Emergency Treatment of Anaphylaxis
Anaphylaxis treatment must be immediate and aggressive to prevent fatal outcomes. The primary treatment is the administration of epinephrine, but additional therapies may be necessary depending on the severity of the reaction. The major steps taken for emergency treatment of anaphylaxis are as follows:
- Epinephrine Auto-Injectors
The first-line treatment for anaphylaxis is an epinephrine injection. Epinephrine works by constricting blood vessels, opening airways, and raising blood pressure, reversing the most dangerous symptoms of anaphylactic shock. Epinephrine auto-injectors (e.g., EpiPen) should be administered as soon as anaphylaxis symptoms are recognized. A second dose may be necessary if symptoms persist after 5-15 minutes.
- Antihistamines
Antihistamines like Benadryl (diphenhydramine) are commonly used to relieve mild allergic symptoms such as hives and itching. However, antihistamines alone are not sufficient to treat anaphylaxis, and their onset of action is slower than that of epinephrine. People often wonder, how long does Benadryl last? The answer is about 4-6 hours, but its role in anaphylaxis treatment is secondary to that of epinephrine.
- Corticosteroids
Corticosteroids may be administered to prevent a biphasic reaction, a second wave of anaphylaxis symptoms that occurs several hours after the initial episode. While not effective immediately, corticosteroids help reduce inflammation and stabilize the immune response over time.
- Intravenous Fluids and Oxygen
In cases of severe shock drop, intravenous fluids are given to restore blood pressure and maintain adequate circulation. Oxygen therapy may be needed if breathing is severely impaired or if the patient is experiencing hypoxia (low oxygen levels). In extreme cases, mechanical ventilation may be required.
- Long-Term Monitoring
Patients should be monitored for several hours after the acute phase, as anaphylactic reactions can recur. This biphasic reaction may occur within 8 to 72 hours after the initial attack. Observation in a medical facility ensures that any secondary reactions are managed promptly.
Top Strategies to Avoid Anaphylaxis Triggers
The best course of action when dealing with allergens is to know the prevention strategies. This may involve avoiding known triggers, preparing for future emergencies, and undergoing desensitization therapy. Fwollng are some of the preventive measures you can adopt to avoid anaphylaxis triggers:
- Allergen Avoidance
Avoidance is the most effective prevention strategy. Individuals with known allergies should take steps to avoid their specific triggers. This includes carefully reading food labels, asking about ingredients when dining out, and ensuring healthcare providers are aware of any medication allergies.
- Carrying an Epinephrine Auto-Injector
Patients with a history of anaphylaxis should always carry an epinephrine auto-injector and know how to use it. Family members, caregivers, and teachers should also be trained to administer epinephrine in case of an emergency.
- Desensitization Therapy
In some cases, allergists may recommend immunotherapy, also known as desensitization. This involves administering gradually increasing doses of the allergen over time, allowing the immune system to become less sensitive to it. This treatment is most commonly used for insect venom allergies but may also be effective for some food or medication allergies.
- Creating an Emergency Action Plan
An emergency action plan outlines what to do in case of anaphylaxis. It includes recognizing the early signs of a reaction, administering epinephrine, and seeking emergency medical care. This plan should be shared with family members, schools, and workplaces to ensure everyone knows how to respond quickly.
Read more: Peanut Allergies: Causes, Symptoms and First Aid
Stay Safe and Prepared for Anaphylaxis!
Anaphylaxis is a severe allergic reaction that can occur rapidly and unexpectedly. Quick access to treatment, including epinephrine, is essential for managing anaphylactic episodes effectively. Individuals at risk should always carry an epinephrine auto-injector and educate those around them about their triggers.
Enrolling in a first aid or basic life support course equips individuals with the necessary skills to respond effectively in such emergencies. Knowledge and readiness significantly enhance the chances of survival during anaphylactic reactions.
