Advrs effect of unsp sys anti-infect and antiparasitic, subs

This code indicates an undesirable or harmful reaction experienced by a patient due to an unspecified systemic anti-infective or antiparasitic medication, occurring during a subsequent encounter for the adverse effect. It signifies that the specific drug causing the reaction is not documented or is unknown, and the patient is receiving ongoing care for the complication.

Use this code when a patient presents for follow-up care, monitoring, or treatment of an adverse effect from a systemic anti-infective or antiparasitic agent, and the specific drug responsible for the reaction is not identified in the medical record. This applies when the initial treatment for the adverse effect has already begun, and the patient is returning for continued management.

• Always sequence this code after the code(s) for the specific manifestation of the adverse effect.
• Avoid using this code if the specific anti-infective or antiparasitic drug is known; instead, use the more specific T36-T37 code with the appropriate 5th or 6th character.
• Ensure the "D" seventh character for "subsequent encounter" is appropriate for the patient's visit, indicating ongoing care for the adverse effect.