Toxic effect of thallium, undetermined, sequela

This code signifies the long-term or residual effects resulting from a past exposure to thallium, where the intent of the exposure (accidental, intentional self-harm, assault) cannot be determined. These sequelae can manifest as neurological damage, gastrointestinal issues, or dermatological conditions that persist after the acute toxic event has resolved.

Apply this code when documenting chronic health problems directly attributable to a previous thallium poisoning of unknown intent. This would be used for follow-up visits or when a patient presents with ongoing symptoms months or years after the initial toxic exposure, and the original circumstances of the poisoning remain unclarified.

• Always sequence this code after the code(s) for the specific sequela(e) being treated (e.g., peripheral neuropathy, alopecia).
• Ensure documentation clearly links the current condition to a past thallium exposure and explicitly states the undetermined intent.
• Do not use this code for acute thallium toxicity; refer to the appropriate acute poisoning codes.