Armodafinil is a prescription medication used to promote wakefulness in individuals with sleep disorders such as narcolepsy, obstructive sleep apnea, and shift work sleep disorder. It is a eugeroic drug, meaning it enhances alertness and reduces excessive daytime sleepiness. Armodafinil is the R-enantiomer of modafinil, offering a longer duration of action, making it effective throughout the day. While it is not a cure for sleep disorders, it helps patients stay awake and function better during their daily activities. Armodafinil should be used under medical supervision to avoid potential side effects.