Adverse effect of antithyroid drugs, sequela

This code signifies a long-term or residual condition resulting from a past adverse reaction to antithyroid medications. It indicates that the patient is experiencing a lasting health problem directly attributable to the previous drug effect, rather than an acute or ongoing adverse event.

This code is appropriate when a patient presents with a chronic or permanent sequela, such as persistent thyroid dysfunction or organ damage, that was caused by an antithyroid drug taken in the past. It should be used after the acute phase of the adverse effect has resolved, and the current condition is a direct consequence.

• Always sequence the code for the specific sequela (e.g., chronic hepatitis, agranulocytosis) first, followed by this code.
• Ensure documentation clearly links the current condition to a past adverse effect of an antithyroid drug.
• Do not use this code for acute or current adverse effects; instead, use the appropriate acute adverse effect code.