Untreated sleepy men with mild to moderate OSA ( age 18-70 , apnoea-hypopnoea index ( AHI ) 5-30 / h , Epworth Sleepiness Scale ( ESS ) 10 ) were randomised to receive 200 mg modafinil or matching placebo daily for 2 weeks before crossing over to the alternative treatment after a minimum 2-week washout .