When Nic is arranging his CDs, the amount of CDs in each of the four columns changes numerous times between shots.
Despite the fact that Nic's addiction story line is shown to cover a number of years, his younger siblings do not ever appear to age.
The poem "Let It Enfold You" by Charles Bukowski is incorrectly named "Let It Unfold You" in the end credits.
Meth does not need to be cooked for injection.
In many of the scenes in airports, characters are shown at the gates greeting other characters/bidding them farewell. Following the September 11, 2001, terrorist attacks, however, no one is allowed past security who isn't a ticket holder. Furthermore, the planes shown in many of these scenes are Boeing 727s, which are not used by the mainstream airlines any longer, and haven't been in decades.
David says Nic has green eyes. About two minutes later they zoom in on the child version of Nic's photo showing him to have dark brown eyes.
In the opening scene, the father describes Nic's hair as "shoulder-length." In fact, it doesn't even cover his ears.