| Hugh Laurie | Dr. Gregory House |
| Lisa Edelstein | Dr. Lisa Cuddy |
| Omar Epps | Dr. Eric Foreman |
| Robert Sean Leonard | Dr. James Wilson |
| Jennifer Morrison | Dr. Allison Cameron |
| Jesse Spencer | Dr. Robert Chase |
| Michael Weston | Lucas Douglas |
| Annabelle Attanasio | Jordan |
| Marcus Giamatti | Keener |
| Bianca Collins | Phoebe |
| Eric Lutes | Derek Retzinger |
| Holly Gagnier | Michelle Berkley |
| Annie Young | Madison |
| Lindsay Johnston | Kaitlin |
| Ana Mackenzie | Avery
(as Ana Lucasey) |
| Rachael Marie | Brianna |
| James R. Bowers | Drummer God |
| Andre Johnson | Dave
(as Andre M. Johnson) |
| Tom Astor | Pharma Guy |
| Michael D. Nye | Joseph Schultz |
| William Christopher Stephens | Man |
| Sharon Swainson | Registration Woman |
| Corey Miguel Curties | Security Guard
(as Corey M. Curties) |
| Bobbin Bergstrom | Nurse |
| DB Albert | Doctor
(uncredited) |
| Sean Field | Pharmacide Bassist
(uncredited) |
| Elsa Morales Myers | Pharmacy Rep /
1980's Party
(uncredited) |
| Alan Mueting | Doctor
(uncredited) |
| William Myers | Pharmacy Rep
(uncredited) |
| Philip Ongert | Pharmacide Publicist
(uncredited) |
| Ron Osburn Jr. | Karate Kid
(uncredited) |
| Lei'lah Star | Kid Patient
(uncredited) |
| Megan Taylor | Stiletto
(uncredited) |