In 1998, the Food and Drug Administration approved the prescription drug modafinil for the treatment of excessive daytime sleepiness in narcoleptics. But this medication has become a star of sorts in the sleep world, gaining popularity and garnering interest beyond narcoleptic circles. It has been put to off-label use as a wake-up pill by those without the sleep condition and its success has paved the way to research that some say could change the future of shuteye.

The interest in sleep is not surprising in a country that does not get enough. Although the average person needs about eight hours of sleep, adults get only an average of seven hours during the workweek, and 36 percent log less than 6.5 hours' sleep on weeknights. One-quarter of adults have even taken sleep medication in the past year.

Before modafinil, the heavy-hitter stimulants of choice for those combating the urge to snooze have been amphetamines such as Dexedrine. But aside from their addictive properties, they caused a range of side effects from agitation, irritability and nausea to increased heart rate, tics and impotence. When the drug wears off, it can lead to a rebound effect that causes extreme fatigue or depression.

Modafinil mostly bypasses the downsides of staying up. "Unlike most wake-promoting drugs, it has very few side effects," says Tom Scammell, M.D., a sleep expert and an assistant professor in neurology at the Beth Israel Deaconess Medical Center in Boston. The most common side effects in patients in clinical trials include headaches (1 percent), nausea (1 percent), depression (1 percent) and nervousness (1 percent).

A June 2000 study published in Psychopharmacologia studied the drug's effects on people's abilities to accomplish demanding tasks despite a lack of sleep. At the United States Army Aeromedical Research Laboratory in Fort Rucker, Alabama, six pilots were kept awake continuously for two forty-hour periods. They were given modafinil in one session and a placebo in the other. The pilots were then evaluated in helicopter simulator flights, resting electroencephalograms (EEGs), and mood questionnaires. The drug lessened the effects of sleep deprivation in four of six flight maneuvers tested compared to the placebo. It also reduced slow-wave EEG activity (when one begins to fall asleep, EEG begins to slow) and decreased self-reported problems with mood and alertness.