The character of Jackson is supposed to be ailing from a werewolf scratch given to him by Derek a few episodes before. Despite having make-up applied, Colton Haynes still looked too healthy so CGI was used to make him look ill.
Dylan O'Brien improvised the line "Don't be such a sour wolf".
Peter Hale's hospital room is actually the office of one of the assistant directors on the show.
The "previously on" at the beginning was said by Tyler Hoechlin (Derek Hale).