Anaphylaxis is a severe, life-threatening hypersensitivity reaction, The pathophysiology of anaphylaxis can be described as immunologic and non-immunologic. Every drug used in anaesthesia reported to cause a reaction, and no premedication has proven to prevent it. NMBAs represent the most frequently incriminated substances followed by latex and antibiotics. Dyes, hypnotic agents, local anaesthetics, opioids, colloids, aprotinin, protamine, chlorhexidine, or NSAIDs are less frequently involved. The clinical presentation of anaphylaxis is a frequent event to all ED and requires prompt recognition and immediate management. Common symptoms and signs include: generalized hives, pruritus, flushing swollen lips-tongue-uvula, periorbital oedema, conjunctival swelling, nasal discharge, nasal congestion, change in voice, choking sensation, stridor, wheeze, cough, shortness of breath. Anaphylaxis may present as mild and resolve spontaneously or it may be severe and may progress within minutes to death. Anaphylaxis always should be considered if immediate hypotension develops following parenteral administration of a therapeutic agent or the induction of anaesthesia. The prevention of peri-anesthetic anaphylaxis is difficult. A careful medical history that focuses on previous adverse reactions is most important. The basic principles of treatment are the same for all age groups. The ABCDE approach is used to recognize and treat an anaphylactic reaction. Early administration of adrenaline immediately benefits the patient which increases the heart rate, blood pressure, and diverts blood to the essential organs such as the heart and brain by dilating their blood vessels and constricting those vessels of less essential organs, such as the skin or peripheries and the renal system.