Modafinil is a stimulant which is often referred to as a “wakefulness-promoting drug” or “eugeroic” because its stimulant activity is relatively subtle. It’s used for conditions characterized by excessive sleepiness and fatigue.

The drug is also taken for cognitive enhancing purposes and to help people remain alert for longer periods. Modafinil is particularly effective at supporting cognitive performance in sleep deprivation.

A number of actions may contribute to the substance’s pharmacology, but the most important actions appear to be connected to dopamine and norepinephrine.