All Modafinil is employed to treat excessive sleepiness caused by narcolepsy (a condition that causes excessive daytime sleepiness) or shift work disorder (sleepiness during scheduled waking hours and difficulty falling asleep or staying asleep during scheduled sleeping hours in folks that work on night or on rotating shifts). Modafinil is additionally used together with breathing devices or other treatments to stop excessive sleepiness caused by obstructive sleep apnea/hypopnea syndrome (OSAHS; a disorder within which the patient briefly stops breathing or breathes shallowly over and over during sleep and so doesn't get enough restful sleep). Modafinil is in an exceedingly class of medicines called wakefulness promoting agents. It works by changing the amounts of certain natural substances within the area of the brain that controls sleep and wakefulness.