Poisoning by thyroid hormones and substitutes, undet, init

This code signifies an adverse event resulting from thyroid hormones or their substitutes, where the intent (e.g., accidental, intentional self-harm, assault) cannot be determined. The patient is in the acute phase of treatment for this poisoning.

Apply this code when a patient presents with symptoms of thyroid hormone toxicity, and the medical record clearly indicates that the circumstances surrounding the exposure are unknown or cannot be definitively classified. This code is appropriate for the initial visit or encounter for this specific poisoning event.

• Always assign an additional code for the specific thyroid hormone involved, if known.
• Do not use this code if the intent of the poisoning is clearly documented (e.g., accidental, intentional self-harm).
• Ensure the "A" seventh character is used only for the initial encounter for this poisoning.