Poisoning by unsp drug/meds/biol subst, accidental, sequela

This code signifies a long-term or residual effect resulting from an accidental poisoning by an unspecified drug, medication, or biological substance. It indicates that the acute phase of the poisoning has passed, but the patient continues to experience health problems directly attributable to the original toxic exposure.

Apply this code when documenting chronic conditions, permanent disabilities, or persistent organ damage that are a direct consequence of a past, unintentional poisoning by an unidentifiable substance. This is used for follow-up encounters after the initial acute poisoning event has resolved.

• Requires a seventh character 'S' to denote sequela, indicating a late effect.
• Always sequence this code after the code(s) identifying the specific sequela (e.g., chronic kidney disease, nerve damage).
• Only use when the specific drug, medicament, or biological substance involved in the original poisoning cannot be identified.