Idiosyncratic alcohol intoxication

This code represents an acute, atypical behavioral or psychological reaction to alcohol consumption that is disproportionate to the amount consumed and not attributable to a pre-existing mental disorder. It signifies an unusual and severe response, such as aggression, violence, or confusion, occurring after ingesting even small quantities of alcohol. This reaction is considered idiosyncratic because it is specific to the individual and not a typical dose-dependent effect.

Use this code when documentation clearly indicates an individual experienced an extreme and uncharacteristic behavioral change following alcohol intake, which is not consistent with typical alcohol intoxication. This diagnosis requires a history of such reactions and the absence of other underlying psychiatric conditions that could explain the behavior. Documentation should specify the atypical nature of the reaction and its disproportionate severity relative to the amount of alcohol consumed.

• Ensure documentation explicitly states "idiosyncratic" or describes an atypical, severe reaction to alcohol that is out of proportion to the amount consumed.
• Differentiate from typical alcohol intoxication (303.0x, 305.0x) or alcohol-induced psychotic disorders (291.5-291.9).
• Consider co-occurring conditions, but this code should be primary when the idiosyncratic reaction is the focus of the encounter.