Poisoning by fentanyl or fentanyl analogs, undet, sequela

This code signifies the long-term effects or complications arising from an exposure to fentanyl or its analogs, where the intent of the poisoning (e.g., accidental, intentional self-harm, assault) cannot be determined. It indicates that the acute phase of the poisoning has passed, and the patient is now experiencing residual health problems directly attributable to the fentanyl exposure.

Apply this code when documenting a patient presenting with chronic conditions, organ damage, or persistent neurological deficits that are a direct consequence of a past fentanyl poisoning event, and the circumstances of that poisoning were never definitively established. This code is appropriate for follow-up care related to such sequelae, rather than the initial acute poisoning episode.

• Always use this code as a secondary diagnosis, following the code for the specific sequela (e.g., anoxic brain damage, chronic kidney disease).
• Ensure documentation clearly links the current condition to a past, undetermined fentanyl poisoning.
• Do not use this code for acute poisoning events; instead, use the appropriate acute poisoning code with the correct intent.