Petey, the guy sitting next to Charlie in the Emergency Room, is portrayed by Joel Murray (one of actor/comedian Bill Murray's brothers), who is the same actor Alan sat next to at the DMV in Mr. McGlue's Feedbag (2007) (s4e22).
Dr. Levine, who attends the birth of Judith's baby, is played by Ken Lerner, who also plays the Delivery Room doctor in Blanche Delivers (1990), a 1990 episode of The Golden Girls (1985).
Charlie Sheen and Ryan Stiles (Dr. Herb Melnick) co-starred in ["link=tt0102059"] and ["link=tt0107144"].