Question: What are the signs and symptoms of anaphylaxis?
Answer: Anaphylaxis is a severe, potentially fatal, sudden-onset systemic allergic reaction that occurs within minutes to hours of exposure to an allergen. So what does that mean? Let's say you're significantly allergic to an allergen and become exposed to that allergen and, over the next few minutes to hours, develops progressive allergic symptoms involving several different organ systems. The organ systems involved include the skin, upper airway, lower airway, gastrointestinal tract and cardiovascular system.
Symptoms in the skin include flushing, itching, swelling and hives. Symptoms in the upper airway include nasal itching, nasal congestion, sneezing and runny nose. Upper airway swelling can occur in the larynx. You can have laryngeal edema with difficulty breathing. Or you can have chest symptoms consisting of coughing, wheezing and shortness of breath. Gastrointestinal symptoms include nausea, vomiting, diarrhea and abdominal cramping. Cardiovascular symptoms include a significant drop in blood pressure, often resulting in a loss of consciousness.
These symptoms can occur either singly or in combination, but in anaphylaxis usually multiple organ systems are involved.