Modafinil

Modafinil, sold under the brand name Provigil among others, is a central nervous system (CNS) stimulant and eugeroic (wakefulness promoter) medication used primarily to treat narcolepsy, a sleep disorder characterized by excessive daytime sleepiness and sudden sleep attacks. Modafinil is also approved for stimulating wakefulness in people with sleep apnea and shift work sleep disorder. It is taken by mouth. Modafinil is not approved by the US Food and Drug Administration (FDA) for use in people under 17 years old.

Common side effects of Modafinil include anxiety, insomnia, dizziness, and headache. Modafinil has potential for causing severe allergic reactions, psychiatric effects, hypersensitivity, adverse interactions with prescription drugs, and misuse or abuse. Modafinil may harm the fetus if taken during or two months prior to pregnancy.

While modafinil is used as a cognitive enhancer, or "smart drug", among healthy individuals seeking improved focus and productivity, its use outside medical supervision raises concerns regarding potential misuse or abuse. Research on the cognitive enhancement effects of modafinil in non-sleep deprived individuals has yielded mixed results, with some studies suggesting modest improvements in attention and executive functions, while others show no significant benefits or even a decline in cognitive functions at high doses.