Modalert 200 australia, which contains modafinil, is seldom used to aid sleep. Modalert 200 is a wakefulness-promoting drug used to treat narcolepsy, OSA, and shift work sleep disorder, which cause excessive daytime drowsiness. modafinil affects brain neurotransmitters including dopamine, norepinephrine, and histamine to improve alertness and minimize tiredness. It keeps people awake, aware, and concentrated.