Allergic reactions occur when the body’s immune system overreacts to substances that are harmless. These substances, known as allergens, can trigger a range of symptoms. While many allergic reactions are mild and resolve without extensive medical intervention, some can escalate rapidly into a severe, life-threatening condition called anaphylaxis. In such instances, immediate emergency medical attention is necessary to stabilize the individual and prevent complications.
Recognizing When to Seek Emergency Care
Knowing the signs of anaphylaxis is important for seeking emergency medical care. Symptoms often appear quickly, within minutes of exposure to an allergen. Indications for an immediate emergency room visit include difficulty breathing, which may manifest as wheezing, shortness of breath, or noisy breathing. Swelling of the face, lips, tongue, or throat may also occur, posing a risk to the airway.
Other serious symptoms include dizziness or fainting, a rapid or weak pulse, and a sudden drop in blood pressure. Extensive skin reactions, such as hives or a rash covering a large area, and persistent vomiting or diarrhea, also signal a severe reaction. Even if initial treatment, such as an epinephrine auto-injector, has been administered and symptoms seem to improve, seeking emergency evaluation is important because symptoms can return hours later in what is known as a biphasic reaction.
Initial Assessment and Stabilization
Upon arrival at the emergency room, individuals experiencing a severe allergic reaction undergo a rapid initial assessment called triage. Medical staff evaluate the reaction’s severity to prioritize interventions. The primary focus is on stabilizing the patient’s airway, breathing, and circulation (ABCs), as these are the body systems most directly impacted by anaphylaxis.
This stabilization involves providing oxygen to support breathing and continuously monitoring vital signs, including heart rate, blood pressure, and oxygen saturation levels. Establishing intravenous (IV) access is a priority, allowing for the rapid administration of necessary medications and fluids. During this phase, the emergency team gathers information about the suspected allergen and the patient’s medical history, which guides further treatment decisions.
Key Medical Interventions
The emergency room employs several medical interventions to counteract the effects of a severe allergic reaction. Epinephrine is the first-line treatment for anaphylaxis due to its rapid action in reversing life-threatening symptoms. This medication works by constricting blood vessels, relaxing muscles in the airways, and reducing swelling, which helps to improve breathing and blood pressure. Depending on the patient’s response, multiple doses of epinephrine may be administered.
Antihistamines, such as diphenhydramine, are used primarily to alleviate skin symptoms like hives and itching. These medications block the effects of histamine released during the allergic reaction. Corticosteroids, like prednisone, may be given to help reduce inflammation and potentially prevent a delayed recurrence of symptoms, although their role in preventing biphasic reactions is still under discussion.
If breathing difficulties persist, bronchodilators, such as albuterol, may be administered via a nebulizer to help open the airways. In cases where blood pressure has dropped significantly, intravenous fluids are given to help restore fluid volume and support circulation. For severe reactions where the airway is severely compromised, advanced airway management, such as intubation, may be necessary to ensure the patient can breathe.
After Emergency Treatment
After the acute symptoms of an allergic reaction are managed, a period of observation in the emergency room follows. This observation period, which can range from a few hours to a longer duration depending on the reaction’s severity and the patient’s response to treatment, is important to monitor for a biphasic reaction. A biphasic reaction is a second wave of symptoms that can occur hours, or sometimes even days, after the initial reaction has seemingly resolved, without further exposure to the allergen.
Before discharge, patients receive instructions on how to manage their condition at home. This guidance includes advice on avoiding the identified allergen. Prescriptions for necessary medications, such as oral corticosteroids or antihistamines, may be provided. Patients are educated on carrying an epinephrine auto-injector, if one has been prescribed, and how to use it correctly. Follow-up with an allergist is recommended for diagnosis, identification of specific triggers, and long-term management strategies.