Joseph Gordon-Levitt

as Adam Lerner

Seth Rogen

as Kyle Hirons

Anna Kendrick

as Katherine McKay

Bryce Dallas Howard

as Rachael

Anjelica Huston

as Diane Lerner

Serge Houde

as Richard Lerner

Philip Baker Hall

as Alan

Matt Frewer

as Mitch

Andrew Airlie

as Dr. Ross

Peter Kelamis

as Phil

Jessica Parker Kennedy

as Jackie

Sugar Lyn Beard

as Susan

Donna Yamamoto

as Dr. Walderson

Yee Jee Tso

as Dr. Lee

Sarah Smyth

as Jenny

Daniel Bacon

as Dr. Phillips

P. Lynn Johnson

as Bernie

Laura Bertram

as Claire

Matty Finochio

as Ted

Marie Avgeropoulos

as Allison

Luisa d'Oliveira

as Agabelle Loogenburgen

Veena Sood

as Nurse Stewart

Andrea Brooks

as Attractive Woman #2

Beatrice King

as Pretty Girl

Chilton Crane

as Mother on the Bus

Lauren Miller Rogen

as Bodie

Jason Vaisvila

as Cute Guy with Dreads

Brent Sheppard

as Minister

Stephanie Belding

as Friendly Nurse

Ryan W. Smith

as Joe

William 'Big Sleeps' Stewart

as George

Amitai Marmorstein

as Young Person on the Bus

Will Reiser

as Greg

Christopher De-Schuster

as Art Gallery Patron

Adrian Glynn McMorran

as Bartender

Karen van Blankenstein

as Nurse Scott

Richard C. Burton

as Thom the Patient

Susan De West

as Bar Girl

Neil Corbett

as Hospital Tech

Stephen Colbert

as Self (archive footage) (uncredited)

D. C. Douglas

as Live Volcano Reporter (voice) (uncredited)

Cameron K. Smith

as Chemo Patient (uncredited)

Tom MacNeill

as Office Staff (uncredited)