Poisoning by histamine H2-receptor blockers, undet, sequela

This code indicates a long-term health problem or complication arising from an H2-receptor blocker overdose or poisoning, where the intent (accidental, intentional, or assault) cannot be determined. The patient is experiencing residual effects of the poisoning event, which occurred in the past.

Use this code when documenting a patient presenting with chronic or residual symptoms directly attributable to a past poisoning by an H2-receptor blocker, and the circumstances of the original poisoning were not specified or are unknown. This applies to follow-up encounters for conditions like persistent organ damage, neurological deficits, or other lasting sequelae.

• Always sequence this sequela code after the code(s) for the specific residual condition(s) being treated.
• Do not use this code for acute poisoning events; those require codes from the initial encounter or subsequent encounter categories.
• Ensure documentation clearly links the current condition to the past H2-receptor blocker poisoning.