Underdosing of antidotes and chelating agents, subs encntr

This code signifies a patient's underdosing of an antidote or chelating agent during a subsequent encounter for the adverse effects. It indicates that the prescribed medication, intended to counteract a poison or remove heavy metals, was taken in a dose lower than recommended, leading to ongoing or unresolved symptoms.

Use this code when a patient presents for follow-up care related to an underdosing of an antidote or chelating agent. This typically occurs when the initial treatment was insufficient, or the patient did not adhere to the prescribed dosage, and they are now experiencing persistent or worsening toxic effects.

• Always assign an additional code for the specific adverse effect or poisoning that necessitated the antidote/chelating agent.
• Ensure documentation clearly states "underdosing" and specifies the type of medication involved.
• Verify this is a "subsequent encounter" as indicated by the 7th character; for initial encounters, use the appropriate 7th character.