A nurse manager is reviewing a recent client report related to a staff nurse. Which of the following behaviors by a nurse at work might be red flags for a substance use disorder?

A. Increased irritability towards supervisors, outspokenness regarding work issues, increased attendance at staff meetings: These behaviors may reflect workplace dissatisfaction or burnout rather than substance use. B. Crying, sharing personal details of relationship problems, monopolizing conversations: These are more indicative of emotional distress or poor boundaries, not necessarily substance use. C. Volunteering for overtime on a continual basis, avoiding having a witness to wasting narcotics, needing to be alone in the medication room when preparing medications: These behaviors suggest potential access and misuse of medications, a key indicator of substance use disorder in healthcare workers. D. Increased cheerfulness, increased energy, helping other nurses on the shift: While these behaviors might seem unusual, they are not strong indicators of substance use disorder.