The medical name of the illness that Heather Evans (Kim Basinger) was said to have in the film was "pathological intoxication" which is a true real-life medical disorder that can exist. Also known as "pathological alcohol intoxication", according to M.H. Hollender in the Journal of Clinical Psychiatry, the condition "appears as a diagnostic term in DSM-II and DSM-III, is defined in a psychiatric dictionary and is described in several textbooks".
In the scene where Isaac confronts Heather in his apartment about giving Diana a gun, the position of Heather's hair changes back and forth throughout the whole scene.