RATIONALE: In 1998, the FDA approved modafinil for treating excessive daytime
sleepiness in narcoleptics, and this has raised questions about the
appropriateness of this compound for enhancing alertness in sleep-deprived
controls. This study explored the efficacy of modafinil for maintaining the
performance of volunteers required to accomplish highly demanding tasks
despite sleep loss.
OBJECTIVE: The principal objective was to determine
whether prophylactic doses of modafinil would attenuate decrements in aviator
performance and arousal throughout 2 days and 1 night without sleep.
METHODS:
Six pilots were exposed to two 40-h periods of continuous wakefulness. In one,
three 200-mg doses of modafinil were given and in the other, matching placebos
were administered. Helicopter simulator flights, resting EEGs, and Profile of
Mood States (POMS) questionnaires were evaluated.
RESULTS: Modafinil
attenuated sleep deprivation effects on four of six flight maneuvers, reduced
slow-wave EEG activity, and lessened self-reported problems with mood and
alertness in comparison to placebo. The most noticeable benefits occurred
between 0330 and 1130 hours, when the combined impact of sleep loss and the
circadian trough was most severe. The most frequently observed drug side
effects were vertigo, nausea, and dizziness. These could have been related to:
1) the motion-based testing, 2) the use of a simulator rather than an actual
aircraft (i.e., "simulator sickness"), and/or 3) the administration
of more than 400 mg modafinil.
CONCLUSIONS: Modafinil is a promising
countermeasure for sleep loss in normals; however, additional studies aimed at
reducing side effects are needed before it should be used in aviators. .
