Toxic effect of venom of centipede/millipede, undet, subs

This code signifies a toxic reaction to venom from centipedes or venomous millipedes where the intent (e.g., accidental, intentional self-harm) is not documented or cannot be determined. The patient is receiving follow-up care for the sequelae of the initial envenomation, such as wound management, ongoing symptom control, or monitoring for delayed complications.

Apply this code for patients presenting for subsequent treatment of symptoms or complications arising from a centipede or venomous millipede bite, when the circumstances surrounding the exposure are unknown or unspecified in the medical record. This is appropriate for office visits, emergency department follow-ups, or inpatient admissions for ongoing management after the initial acute phase.

• Always assign an external cause code (e.g., X22.-) in conjunction with this code to provide more detail about the exposure, if known.
• Ensure the "D" seventh character is appropriate for subsequent care; use "A" for initial encounters and "S" for sequelae.
• If the intent of the exposure is clearly documented (e.g., accidental, assault), select a more specific T63.41- code.