Introduction: Anaphylaxis is the most severe and potentially lethal presentation of acute systemic allergic reactions. Understanding its mechanisms provides a better diagnostic and therapeutic approach. Objective: to present the key concepts of the mechanisms of anaphylaxis, its diagnosis, and its management in clinical practice. Methods: a summary of the main concepts on the mechanisms, diagnosis, and management of anaphylaxis in clinical practice was made according to the review presented at the congress of the Asociación Colombiana de Medicina Interna (ACMI) Capítulo Valle, Universidad Libre: "A multidisciplinary approach with a Latin American vision" on May 13th and 14th, 2022. Results: Anaphylaxis may affect 5% of people at some time in their lives. The main allergens are drugs, food, and Hymenoptera venom, but the cause may vary throughout the life cycle. The diagnosis is made according to the criteria of the World Allergy Organization and is confirmed by the determination of serum tryptase in case of doubt. Adrenaline intramuscular is the first line of treatment. Once the episode is over, evaluation by an allergy expert is always necessary. Conclusion: identification and adequate treatment of anaphylaxis save lives. In the approach to the patient with anaphylaxis, it is important to identify the allergen and the factors associated with the episode to prevent a new one.