A 20 year old man has presented with increased alcohol consumption and sexual indulgence, irritability, lack of sleep, and not feeling fatigued even on prolonged periods of activity. All these changes have been present for 3 weeks. The most likely diagnosis is -

Diagnostic criteria for mania Three or more of the following for at least 1 week:- Inflated self esteem or grandiosity     Decreased need for sleep        Overtalkativeness   Flight of ideas Distractibility Psychomotor agitation or Increased goal-directed activities Excessive involvement in pleasurable activities Coming to question This patient has (for 3 weeks):- Decreased need for sleep Excessive involvement in pleasurable activities (sexual indulgence, increased alcohol consumption) Increased activity (prolonged period of activity) Diagnosis is mania.