Subjective Effects of Modafinil in Military Fighter Pilots During Deployment.

Fatigue has negative effects on flight safety, especially in military aviation, where missions are often performed under challenging conditions. Modafinil is a relatively new pharmaceutical able to counter the symptoms of fatigue, but efficacy has not yet been studied in operational military aviation. This study aims to establish effectiveness and safety of modafinil in military operations. This field study was conducted during deployment in the Middle East by the Royal Netherlands Air Force fighter pilots. Prior to use operationally, pilots had to complete a 24-h ground test in which modafinil was administered during a nonflying period using a questionnaire to screen for duty-relevant side effects. If no side effects were reported, operational usage was allowed. In addition to registration of modafinil's effects, relevant data prior to and after administration were recorded, including caffeine consumption and sleep afterwards. Of the 75 pilots who completed ground testing, only one experienced duty-relevant side effects. Modafinil was used in 192 operational flights, mostly during night-time. In 128 (67%) of the flights, modafinil was used preventively, in 64 (33%) because of fatigue. In 182 (95%) of the flights, positive effects of modafinil were reported, with a maximum effect 2-3 h after administration. There was no statistical correlation between modafinil's beneficial effects and prior administration of caffeine or sleep medication, nor was sleep afterwards negatively affected. This study indicates modafinil is a suitable pharmaceutical countermeasure to minimize the effects of fatigue during real-life fighter operations, without signs of negative impact on flight safety or sleep quality afterwards.