Armodafinil (trade name Nuvigil) is the enantiopure compound of the eugeroic modafinil (Provigil). It consists of only the (R)-(−)-enantiomer of the racemic modafinil. Armodafinil is produced by the pharmaceutical company Cephalon Inc. and was approved by the U.S. Food and Drug Administration (FDA) in June 2007. In 2016, the FDA granted Mylan rights for the first generic version of Cephalon's Nuvigil to be marketed in the U.S. Because armodafinil has a longer half-life than modafinil does, it may be more effective at improving wakefulness in patients with excessive daytime sleepiness. Medical uses Armodafinil is currently FDA-approved to treat excessive daytime sleepiness associated with obstructive sleep apnea, narcolepsy, and shift work disorder. It is commonly used off-label to treat attention deficit hyperactivity disorder, chronic fatigue syndrome, and major depressive disorder, and has been repurposed as an adjunctive treatment for bipolar disorder. It has been shown to improve vigilance in air traffic controllers, however in the United States, sleep prevention medications such as Provigil (Modafinil) and Nuvigil (Armodafinil) are not approved by the FAA for civilian controllers or pilots. Psychiatry Bipolar disorder Armodafinil, along with racemic modafinil, has been repurposed as an adjunctive treatment for acute depression in people with bipolar disorder. Meta-analytic evidence showed that add-on modafinil and armodafinil were more effective than placebo on response to treatment, clinical remission, and reduction in depressive symptoms, with only minor side effects, but the effect sizes are small and the quality of evidence has to be considered low, limiting the clinical relevance of current evidence. Schizophrenia In June 2010, it was revealed that a phase II study of armodafinil as an adjunctive therapy in adults with schizophrenia had failed to meet the primary endpoints, and the clinical program was subsequently terminated. However, a study published later that year showed that patients with schizophrenia treated with armodafinil showed fewer of the negative symptoms of schizophrenia. Jet lag On March 30, 2010, the FDA declined to approve use of Nuvigil to treat jet lag. Adverse effects In placebo-controlled studies, the most commonly observed side effects were headache, xerostomia (dry mouth), nausea, dizziness, and insomnia. Possible side effects also include depression, anxiety, hallucinations, euphoria, extreme increase in activity and talking, anorexia, tremor, thirst, rash, suicidal thoughts, and aggression. Symptoms of an overdose on armodafinil include trouble sleeping, restlessness, confusion, disorientation, feeling excited, mania, hallucinations, nausea, diarrhea, severely increased or decreased heart beat, chest pain, and increased