Toxic eff of harmful algae and algae toxins, slf-hrm, subs

This code signifies a patient presenting for follow-up care related to a toxic exposure from harmful algae or algae toxins, where the exposure was intentionally self-inflicted. The patient is experiencing ongoing effects or complications from a prior act of self-poisoning using these substances.

Apply this code for subsequent encounters when a patient is being managed for the sequelae of a deliberate self-poisoning attempt involving harmful algae or their toxins. This includes follow-up appointments for symptom management, monitoring for organ damage, or mental health evaluations related to the initial self-harm event. It is appropriate after the initial acute treatment has been rendered.

• Always sequence this code after the primary diagnosis describing the specific manifestation of the toxic effect.
• Ensure documentation clearly indicates "intentional self-harm" and that the encounter is not the initial treatment for the acute event.
• Pair with an external cause code (e.g., X64.-) to fully describe the circumstances of the self-harm.