Poisoning by oth vaccines and biolg substances, undet, init

This code signifies an adverse reaction or toxicity resulting from the administration of a vaccine or other biological substance, where the intent (e.g., accidental, intentional self-harm, assault) cannot be determined. The patient is experiencing the initial phase of care for this poisoning event.

Apply this code when a patient presents with symptoms of poisoning due to a vaccine (e.g., flu shot, tetanus shot) or other biological product (e.g., antitoxin, immunoglobulin), and the provider documentation does not specify whether the exposure was accidental, intentional, or due to assault. This code is appropriate for the first encounter related to this specific poisoning.

• Always sequence this code first if it is the primary reason for the encounter.
• Requires additional codes to specify the specific vaccine or biological substance involved (e.g., from categories T50.B- or T50.Z-).
• Do not use if the intent of the poisoning is clearly documented as accidental, intentional self-harm, or assault; refer to the appropriate intent subcategory.