Hyperactive delirium is best characterized by which symptom cluster?

• A. Lethargy and decreased responsiveness
• B. Sleep-wake reversal without agitation
• C. Restlessness, agitation, irritability, and aggression
• D. Drowsiness with minimal movement

Answer: (C)

Hyperactive delirium presents with a burst of motor and behavioral activity driven by acute brain dysfunction. The hallmark symptom cluster is restlessness with agitation and irritability, often accompanied by aggression. This pattern reflects heightened arousal and disruptive behavior, setting it apart from hypoactive delirium, where lethargy, decreased responsiveness, and minimal movement are prominent. Sleep-wake reversal can occur in delirium overall, but the defining feature of the hyperactive type is the prominent motor agitation and behavioral dysregulation. Recognizing this pattern is crucial for ensuring safety, prompt assessment for precipitating factors (such as infection, metabolic disturbances, or medication effects), and timely management.