Introduction: Successful military aviation operations depend on maintaining continuous day-night operations. Stimulants are easy to use and popular for sustaining performance because their utility is not dependent upon environmental or scheduling modifications. Dextroamphetamine is authorized for use by the aircrews of all U.S. military services, but its potential for abuse and subsequent addiction is of aeromedical concern. Finding an alternative stimulant, such as modafinil, that displays a low affinity for dopamine uptake binding sites would prove extremely beneficial. This study sought to establish the efficacy and safety of modafinil during actual flying operations, thus providing the operational validity desired to approve the use of modafinil for helicopter flight operations.
Methods: During two, 40-h periods of sustained wakefulness, 18 helicopter pilots (17 men, 1 woman, mean years of age = 29.5) each completed 15 flights and other evaluations, during which they received 2 of 3 experimental conditions: 3 doses at 4-h intervals of modafinil (100 mg), dextroamphetamine (5 mg), or placebo.
Results: Statistical results showed that modafinil, like dextroamphetamine, maintained alertness, feelings of well-being, cognitive function, judgment, risk perception, and situation awareness of sleep-deprived aviators consistently better than placebo and without side effects of aeromedical concern.
Discussion: Like previous research, this study strongly suggests that both drugs can maintain acceptable levels of mood and performance during sleep deprivation. The results also confirm that modafinil is well tolerated and appears to be a good alternative to dextroamphetamine for countering the debilitating mood and cognitive effects of sleep loss during sustained operations.