Underdosing of other opioids, initial encounter

This code signifies a patient experiencing adverse effects due to taking less than the prescribed or intended dose of an opioid other than heroin or methadone. It indicates a situation where the therapeutic effect of the opioid is insufficient due to underdosing, potentially leading to a return of symptoms or withdrawal.

Apply this code when a patient presents with symptoms directly attributable to not taking enough of their prescribed opioid medication (e.g., oxycodone, hydrocodone, fentanyl patches) and this is the initial encounter for this specific underdosing event. This could include scenarios where a patient intentionally takes less due to fear of addiction, forgets doses, or mismanages their medication supply.

• Ensure the documentation clearly states the patient took less than the prescribed dose of an opioid other than heroin or methadone.
• Verify this is the initial encounter for the underdosing event; subsequent encounters would use the appropriate subsequent encounter character.
• Distinguish from poisoning (overdosing) or adverse effects from correct dosing, which are coded differently.