Poisoning by tetracyclic antidepressants, undetermined, subs

This code signifies a poisoning event involving tetracyclic antidepressants where the intent (accidental, intentional self-harm, assault) is unknown or cannot be determined. It specifically applies to encounters following the initial treatment of the acute poisoning.

Use this code for follow-up visits, such as medication management, monitoring for long-term effects, or further diagnostic workup, after a patient has been treated for an acute tetracyclic antidepressant poisoning of unknown intent. This applies when the initial acute phase has passed, and the patient is no longer in the emergency or inpatient setting for the immediate poisoning.

• Always assign an additional code for the specific manifestation(s) of the poisoning, if applicable.
• Do not use this code for the initial encounter; use the corresponding acute (A) or initial (D) encounter code.
• Ensure documentation clearly supports the "undetermined" intent and that it is a subsequent encounter.