Poisoning by histamine H2-receptor blockers, self-harm, init

This code signifies a patient presenting with adverse effects resulting from the deliberate overdose or misuse of histamine H2-receptor blockers (e.g., cimetidine, ranitidine, famotidine) with the intent to harm themselves. The patient is in the initial phase of receiving active treatment for this poisoning.

Apply this code when documenting an emergency department visit or initial inpatient admission for a patient who intentionally ingested an excessive amount of an H2-receptor blocker. This would include cases where the patient explicitly states self-harm intent or when clinical evidence strongly suggests such intent, and they are undergoing initial diagnostic workup and treatment.

• Always assign an additional code for the specific H2-receptor blocker involved, if known (e.g., T47.0X1- for cimetidine).
• Ensure documentation clearly supports the "intentional self-harm" intent; otherwise, consider codes for accidental poisoning or adverse effect.
• The "initial encounter" character indicates the patient is receiving active treatment for the poisoning, not follow-up care.