BACKGROUND: Armodafinil (Nuvigil(®), Cephalon, Inc., Frazer, PA, USA), the longer-lasting isomer of racemic modafinil, is a nonamphetamine, wakefulness-promoting medication. In patients with excessive sleepiness associated with shift work disorder, treated obstructive sleep apnoea, or narcolepsy, armodafinil has been found to improve wakefulness throughout the shift or day. In addition, while not approved for this indication, armodafinil has been found to improve excessive sleepiness associated with jet-lag disorder.