Reparto
Chris Rock
Osmosis Jones (voice)
Laurence Fishburne
Thrax (voice)
David Hyde Pierce
Drix (voice)
Brandy Norwood
Leah (voice)
Elena Franklin
Shane Detorre
Bill Murray
Frank Detorre
William Shatner
Mayor Phlegmming (voice)
Ron Howard
Tom Colonic (voice)
Kid Rock
Kidney Rock (voice)
Molly Shannon
Mrs. Boyd
Chris Elliott
Bob
Jonathan Adams
Officer Tom (voice)
Carlos Alazraqui
Spanish Germ (voice)
Eddie Barth
Conductor (voice)
Sally Brooks
Additional Character Voices (voice)
Rodger Bumpass
Joe Cramp / Announcer for Nerve News Network (voice)
Janis Dardaris
Additional Character Voices (voice)
Antonio Fargas
Chill the Flu Shot (voice)
Eddie Frierson
Frank Police Department Officer (voice)
Donald Fullilove
Doughnut (voice)
Jackie Gonneau
Additional Character Voices (voice)
Richard Steven Horvitz
Additional Character Voices (voice)
Rif Hutton
Charlie (voice)
Anne Lockhart
Female Red Blood Cell (voice)
Sherry Lynn
Trudy (voice)
Danny Mann
Musician Cell (voice)
Mickie McGowan
Brain Librarian (voice)
Joel Silver
Police Chief (voice) (uncredited)
John Melendez
Artie (voice)
Héctor Mercado
Additional Character Voices (voice)
Paul Pape
Male Red Blood Cell #2 (voice)
Chris Phillips
Firefighter Doug (voice)
Al Rodrigo
Frank Police Department Walkie Talkie (voice)
Herschel Sparber
Bruiser (voice)
Keri Tombazian
Additional Character Voices (voice)
Paul Tuerpe
Additional Character Voices (voice)
Robert Wisdom
Big Germ (voice)
Danny Murphy
Zookeeper Superintendent
Jackie Flynn
School Janitor
Abe Farrelly
Bus Girl #2
John-Eliot Jordan
Pea Soup Manager
Kevin J. Flynn
Docky's Clamshack Waiter
Sean Gildea
Dreamy Photographer
Nikki Tyler-Flynn
Nurse #2
Zen Gesner
ER Doctor #1
Zak Penn
ER Doctor #3
