Poisoning by antithyroid agents

This code signifies an adverse effect resulting from the ingestion or exposure to antithyroid medications. This includes conditions like agranulocytosis, liver damage, or severe allergic reactions caused by drugs such as methimazole or propylthiouracil (PTU). It represents the physiological harm or illness directly attributable to the antithyroid agent.

Use this code when a patient presents with symptoms or conditions directly linked to an overdose, adverse reaction, or improper use of antithyroid drugs. Documentation should clearly state the antithyroid agent involved and the resulting clinical manifestation of the poisoning. This code is appropriate for both accidental and intentional poisonings.

• Always sequence this code as the primary diagnosis when the poisoning is the reason for the encounter.
• Utilize an E-code (E850.1 for accidental, E950.3 for suicide attempt, E980.3 for undetermined) to identify the external cause of the poisoning.
• Do not confuse with adverse effects from therapeutic use (995.2x series) unless the intent was clearly an overdose or misuse.