Allergy status to serum and vaccine

This code indicates a patient's documented history of an adverse reaction or sensitivity to serum products or vaccines. It signifies an allergic status, not an active allergic reaction, and is used to alert healthcare providers to potential risks with future administration of these substances.

Apply this code when a patient's medical record clearly states a past allergic response to any type of serum (e.g., antivenom, antitoxin) or vaccine (e.g., flu vaccine, tetanus shot). This is particularly relevant for pre-procedural assessments, immunization planning, or when considering administration of biological products.

• Always ensure the documentation specifies an "allergy status" or "history of allergy" rather than an active allergic event.
• Do not use this code for adverse effects that are not allergic in nature (e.g., fever, soreness at injection site).
• Consider using additional codes to specify the particular serum or vaccine if known and if there's a more specific Z-code available (e.g., Z91.01- for specific drug allergies).