Poisn by immune chkpt inhibtr/immunostim drugs, acc, subs

This code signifies an adverse event resulting from the unintentional ingestion or administration of immune checkpoint inhibitors or other immunostimulant medications. The patient is experiencing ongoing effects or complications from this poisoning, and this encounter is for follow-up care, monitoring, or treatment after the initial presentation.

Apply this code when a patient presents for subsequent management of poisoning by immune checkpoint inhibitors or immunostimulant drugs due to an accidental overdose, incorrect dosage, or mistaken identity of the medication. This includes situations where the patient is returning for further evaluation of organ damage, immune-related adverse events, or to adjust ongoing treatment related to the poisoning.

• Requires an external cause code (V00-Y99) to describe the circumstances of the poisoning.
• Always sequence this code after the primary diagnosis describing the specific manifestation of the poisoning (e.g., acute kidney injury, hepatitis).
• Distinguish from intentional self-harm or assault, which would use different intent characters.