Anaphylaxis

Sudden onset of respiratory or cardiovascular compromise, usually with a history of allergen exposure in sensitized individuals.

Skin rash, wheezing and inspiratory stridor, hypotension, anxiety, nausea, and vomiting are the cardinal signs and symptoms.

The diagnosis is clinical. Allergy testing is helpful only for secondary prophylaxis.

Securing the airway and initiating prompt treatment with epinephrine (adrenaline) may save lives.

Comorbidities (e.g., coronary artery disease and COPD) may pose a treatment challenge and warrant expert consultation

Anaphylaxis is an acute, severe, life-threatening allergic reaction in presensitized individuals, leading to a systemic response caused by the release of immune and inflammatory mediators from basophils and mast cells. At least two organ systems are involved, such as the skin, the upper and lower airways, and the cardiovascular, neurologic, and gastrointestinal systems, in this order of priority or in combination. Allergy to medications, food, immunotherapy, or insect stings is the most frequent cause. Nonimmunologic anaphylaxis, previously described as an anaphylactoid reaction, produces similar symptoms.