Omar Epps
Dr. Eric Foreman (119 episodes, 2004-2009)
Olivia Wilde
Thirteen - Dr. Hadley / ... (45 episodes, 2007-200
Kal Penn
Dr. Lawrence Kutner (36 episodes, 2007-2009)
Anne Dudek
Dr. Amber Volakis (18 episodes, 2007-2009)
Sela Ward
Stacy Warner (9 episodes, 2005-2006)
Edi Gathegi
Dr. Jeffrey 'Big Love' Cole (7 episodes, 2007)
Cindy Lu
Nurse / ... (4 episodes, 2005-2009)
Liz Benoit
Nurse Anne / ... (4 episodes, 2007-2009)
Eamon Hunt
Neurosurgeon #1 / ... (2 episodes, 2005-2006)
R. Lee Ermey
Colonel John House / ... (2 episodes, 2005-2008)
David Pearl
Concert Hall Patron / ... (2 episodes, 2007-2009)