Other serum reaction due to other serum, sequela

This code signifies a delayed or long-term adverse effect resulting from a serum or antitoxin administration, excluding those specifically categorized elsewhere. It covers a range of non-immediate, systemic reactions that manifest after the initial treatment with a biological product derived from animal or human serum.

Apply this code when documenting a chronic or persistent condition that is a direct consequence of a past serum or antitoxin infusion. Examples include persistent arthralgia, nephritis, or neurological symptoms that developed weeks or months after the original serum exposure.

• Always use in conjunction with an external cause code (Y40-Y59) to identify the specific serum or antitoxin involved.
• Ensure documentation clearly links the current condition to a previous serum administration.
• This code is for sequelae; do not use for acute or immediate serum reactions.