For narcolepsy, or off-label for depression, night-shift work, ADHD/ADD...a prodrug, metabolizes to modafinil (Provigil®), resulting in nearly identical pharmacological effects, takes 45-60 minutes to reach active levels in bloodstream.
Eugeroic = “good arousal." Unique class of drugs (adrafinil, modafinil). Like adaptogens (ginseng), only “stimulate when stimulation is required.” Highs and lows associated with other stimulants (amphetamine, etc) are absent with eugeroics.