Anaphylaxis is a severe, potentially life-threatening allergic reaction that can be triggered by a variety of causes, most commonly certain medications, foods, and insect bites. However, the cause in up to one in five cases of anaphylaxis is unknown.
Anaphylaxis is a condition where the body’s immune system reacts by overreacting to the trigger allergen that sets in motion a rapid, body-wide allergic reaction. This reaction may cause many varying symptoms affecting several systems of the body. It may begin mildly but progress rapidly. Symptoms may begin with a feeling of doom or anxiety before physical symptoms occur.
Healthcare providers most of the time diagnose anaphylaxis when symptoms affect at least two body systems. Common symptoms of anaphylaxis include
- Skin symptoms such as the appearance of hives
- Respiratory symptoms such as difficulty breathing
- Cardiovascular symptoms such as hypotension
- Gastrointestinal symptoms like nausea and vomiting
Anaphylaxis usually starts within an hour of exposure to a trigger. Treatment with epinephrine, such as an EpiPen, is very important to stop the body’s immune response. Without treatment, anaphylaxis can be fatal. Half of all cases of anaphylaxis occur at home, so it is important to recognize the symptoms and take action right away.
Skin Symptoms
Another criterion that healthcare providers use to diagnose anaphylaxis is that skin symptoms occur with other forms of symptoms. One of the most common and earliest signs of anaphylaxis includes hives, known as urticaria. Most anaphylactic reactions include skin symptoms, although sometimes they do not.
- Hives: These are raised, red welts on the skin. They can differ in size or shape. The hives appear in one region of the body or spread widely over large sections.
- Flushing is the red coloration of skin, possibly seeming like a sunburn.
- Most commonly, the flushing occurs across the face, neck, and chest.
- Itching up to half the adults who encounter anaphylaxis have all-over itching.
Swelling: Swelling tends to appear in the face, lips, tongue, or even the throat. Swelling around the airways is extremely hazardous since this affects respiration.
Respiratory Symptoms
Respiratory symptoms are the most hazardous during an anaphylactic reaction. This is because they can quickly lead to life-threatening complications. While these symptoms may begin with a simple runny nose or congestion, they will quickly progress to more serious symptoms. Respiratory symptoms of anaphylaxis include
Trouble breathing (dyspnea): Up to two-thirds of adults with anaphylaxis experience shortness of breath or labored breathing. This may result in the blood becoming significantly low in oxygen (hypoxemia). In the worst cases, if the swelling caused by anaphylaxis closes off your airways completely, you may be completely unable to breathe.
- Wheezing or stridor: These are high-pitched whistling sounds when you breathe. These may indicate that your airways have narrowed. Wheezing sounds usually more musical than stridor, which can sound a bit more squeaky.
- Throat tightness or fullness: You might feel as if you are having trouble swallowing or speaking due to a feeling that your throat is closing up or blocked.
- Hoarse voice: Hoarseness can be an indication of how anaphylaxis is affecting your airways.
- Coughing: Ongoing cough that fails to resolve with usual treatment can be indicative of obstruction in the airways.
Cardiovascular Symptoms
Anaphylaxis may impact parts of the cardiovascular system, which consists of the heart, arteries, veins, and capillaries. Symptoms from this system may be fatal and can include
Chest pain: You could feel chest pain or pressure during an anaphylactic reaction
- . You may easily confuse this symptom with a heart attack.
- Hypotension: Low blood pressure is a serious symptom since it could imply your heart is struggling to pump enough blood to the vital organs. Sudden lowering of blood pressure can cause dizziness or even fainting.
- Rapid heartbeats: Your heartbeat can become rapid due to an attempt by your body to compensate for the lowering of blood pressure.
- Weak pulse: As anaphylaxis progresses, your pulse may become weaker.
Gastrointestinal Symptoms
A range of gut symptoms may occur when anaphylaxis affects the digestive system. Up to a third of adults with anaphylaxis experience gastrointestinal symptoms. These symptoms may be
- Nausea and vomiting: Sudden nausea and vomiting can occur as your body reacts to the allergen.
- Diarrhea: Loose or watery stools can be another sign of anaphylaxis.
- Abdominal pain or cramping: Severe stomach pains or cramps; possibly accompanied by nausea and vomiting or diarrhea.
Symptoms in Children
In some cases, different triggers may present symptoms of anaphylaxis in children compared to adults. In adults, for example, drugs represent the most frequent trigger while, in children, food represents it. Some common food allergens include peanuts, milk, and eggs.
- Children are more likely than adults to experience hives as an anaphylaxis symptom.
- They are also more likely to experience respiratory symptoms including stridor, wheezing, cough, and shortness of breath.
- Children are less likely than adults to have cardiovascular symptoms.
- Healthcare providers are more likely to miss gastrointestinal and respiratory symptoms in children when diagnosing anaphylaxis.
When to Contact a Healthcare Provider
Although they may begin mild, anaphylaxis symptoms can become life-threatening within minutes. If you have symptoms such as swelling of the throat or difficulty breathing, especially after exposure to something you are allergic to, use an EpiPen immediately. If you do not have access to an EpiPen, call 911 or ask someone to take you to an emergency room (ER) for treatment. Be sure to seek medical care even after using an EpiPen.
After you have treated the initial symptoms of an anaphylactic reaction, there is a chance symptoms will return up to 72 hours after treatment.7This is called a biphasic reaction. A biphasic reaction can happen in up to 20% of people who have recently had anaphylaxis.4Tell your healthcare provider right away or go to the ER if you notice any symptoms returning.
Quick Review
Anaphylaxis is a fast-developing allergic reaction that can affect several organs and systems in the body. Identifying the signs of anaphylaxis can protect you from terrible complications which can be fatal. The most common symptoms involve hives, itching, trouble breathing, chest pain, and nausea.
Children may display symptoms of anaphylaxis differently than adults but can have symptoms in their skin, respiration, heart, and GI tract. Never delay seeking immediate medical attention, even if you have used an EpiPen, because half of the deaths associated with anaphylaxis happen within one hour.
