The scene in the dentist office was improvised.
Shot in twenty-two days.
Anna Faris was cast in the role of Maggie, but after a long time in development she was replaced by Kristen Wiig.
Bill Hader and Kristen Wiig have worked together many times before. In addition to the many seasons of Saturday Night Live (1975), on which they worked simultaneously, at the time this movie was filmed, they had already appeared in over half a dozen films in common, including Adventureland (2009), Knocked Up (2007), Forgetting Sarah Marshall (2008), Paul (2011), Ice Age: Dawn of the Dinosaurs (2009), The Brothers Solomon (2007), and Her (2013).