Osmosis Jones

Chris Rock

Osmosis Jones (voice)

Laurence Fishburne

Thrax (voice)

David Hyde Pierce

Drix (voice)

Brandy Norwood

Leah (voice)

Bill Murray

Frank Detorre

Elena Franklin

Shane 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)

Steve Susskind

Mob Boss Germ (voice)

Robert Wisdom

Big Germ (voice)