Jessica Alba as Sydney Wells

Alessandro Nivola as Dr. Paul Faulkner

Parker Posey as Helen Wells

Chloë Grace Moretz as Alicia Millstone

Rade Šerbedžija as Simon McCullough

Mia Stallard as Little Girl

Obba Babatundé as Dr. Haskins

Danny Mora as Miguel

Rachel Ticotin as Rosa Martinez

Tamlyn Tomita as Mrs. Cheung

Karen Elizabeth Austin as Mrs. Hillman

Fernanda Romero as Ana Christina Martinez

Heather Doerksen as Sickly Woman

Tegan Moss as Teenage Girl

Rachel Manera as Nurse (uncredited)

Braden Wilcox as Children's Ward Cancer Patient (uncredited)