Armod 150 mg is used to treat shift work sleep disorder as well as narcolepsy, two disorders which cause excessive daytime sleepiness. (sleepiness during scheduled waking hours and difficulty falling asleep or staying asleep during scheduled sleeping hours in people who work at night or on rotating shifts). To help to prevent the excessive sleepiness caused on by the obstructive sleep apnea/hypopnea syndrome, modafinil is also used together with breathing devices or other treatments. Armodafinil comes to a group of medications known as wakefulness-promoting medications. It works through changing the concentrations of certain natural substances in the region of the brain that controls wakefulness and sleep.