• Tertiary anticholinenergic drugs (atropine and scopolamine) can cross the blood brain barrier and lead to postoperative delirium. 
  • Glycopyrrolate is a quarternary agent and does not cross the blood brain barrier. 
  • Propofol is associated with rapid recovery and euphoria. 
  • Long acting benzodiazpines may also contribute to disorientation on emergence. In young healthy patients recovery from midazolam is generally not associated with
  • disorientation. 
  • Meperidine, although rare, because of its atropine-like structure can cause post-operative agitation and combativeness.