Eugeroics (originally "eugrégorique" or "eugregoric"),^[1] also known as wakefulness-promoting agents and wakefulness-promoting drugs, are a class of drugs that promote wakefulness and alertness.^[2][3] They are medically indicated for the treatment of certain sleep disorders including excessive daytime sleepiness (EDS) in narcolepsy or obstructive sleep apnea (OSA).^[2][3] Eugeroics are also often prescribed off-label for the treatment of EDS in idiopathic hypersomnia.^[4] In contrast to classical psychostimulants, such as methylphenidate and amphetamine, which are also used in the treatment of these disorders, eugeroics typically do not produce marked euphoria, and, consequently, have a lower addictive potential.^[2][3][5]

Modafinil and armodafinil are each thought to act as selective, weak, atypical dopamine reuptake inhibitors (DRI),^[2][3] whereas adrafinil acts as a prodrug for modafinil. Other eugeroics include solriamfetol, which acts as a norepinephrine–dopamine reuptake inhibitor (NDRI),^[6][7] and pitolisant, which acts as a histamine 3 (H₃) receptor antagonist/inverse agonist.^[8][9][10]

Cephalon, the original U.S. market rights holder of modafinil, has demonstrated initiative in the development of a successor to the prototypical eugeroic.^[11] Of the more than twenty compounds preclinically tested in Cephalon's three-part drug discovery series, the compound fluorenol was selected as a lead. Fluorenol was found to induce wakefulness to a greater degree than modafinil, despite possessing a lower affinity for the dopamine transporter.^[12]

All currently marketed eugeroics are classified as central nervous system stimulants and possess some (attenuated) stimulant-like properties.^[13][14] It is expected that future developments will further distinguish eugeroics from classical CNS stimulants.^[15][11]