Edward Asner appears in this episode as a doctor named "James McNulty", which is also the name of the lead character on The Wire (2002), which first aired a little over six months before this episode aired. McNulty's supervisor on that show is played by John Doman, who plays the psychiatrist Dr. Carl Deraad here.
Shoshannah Stern and Liz Torres are both in this episode. They have both worked alongside Jared Padalecki who was also in an episode of ER. Shoshannah Stern worked with him on Supernatural (2005) and Liz Torres worked with him in Gilmore Girls (2000).