Modafinil and Armodafinil – Mechanism of Action | Psychopharmacology | Clinical Application

Posted on:July 21, 2021
Last Updated: November 24, 2023
Time to read: 10 minutes

Modafinil is a synthetic non-amphetamine stimulant approved for the first-line treatment of excessive sleepiness (ES). [Mignot, 2004]

Modafinil is a racemate, with the two enantiomers conferring approximately equipotent effects on the brain, although the R-isomer has a different pharmacological profile: 

  • Modafinil is a racemic mixture (R– and S-isomers) of diphenylmethylsulfinylacetamide  

Modafinil is indicated for ES caused by narcolepsy and sleep work shift disorder (SWSD) and obstructive sleep apnoea with continuous positive airway pressure use (res-OSA).

Armodafinil, like modafinil, is also a wakefulness promoter indicated for ES associated with narcolepsy, SWSD, and res-OSA. 

However, it is important to note that in 2011 the European Medicines Agency removed the SWSD and res-OSA indications and restricted modafinil to the treatment of narcolepsy.