Anaphylactic shock, unspecified, initial encounter

This code signifies a severe, life-threatening systemic allergic reaction characterized by a sudden drop in blood pressure, airway constriction, and widespread vasodilation, where the specific cause of the anaphylaxis is not yet identified. It represents the initial episode or encounter for this acute condition.

Use this code when a patient presents with clear signs and symptoms of anaphylactic shock, such as respiratory distress, hypotension, and skin manifestations, but the allergen responsible has not been determined. It is appropriate for the first time a patient is seen for this specific episode of anaphylaxis.

• Only use for the initial encounter of an unspecified anaphylactic shock. Subsequent encounters for the same episode would use a different seventh character.
• Avoid using this code if the specific allergen causing the anaphylaxis is known; instead, code the specific type of anaphylactic shock (e.g., due to food, drug).
• Always sequence this code first if it is the primary reason for the encounter.