**Conflict of interest**

true [43]. All in all, one can have an energy drink that has about the same effect as 1–3 cups

Modafinil was originally developed as a treatment against narcolepsy, a disease that has sleep attacks and severe sleepiness as one of its core symptoms. Modafinil has been shown to have a moderate but significant effect on reducing sleepiness and the number of car accidents in shift work [44]. Recently, it has been shown to improve driving in real conditions in patients with

Modafinil thus increases wakefulness, alertness, concentration and decreases fatigue and sleepiness. It could slightly reduce appetite. It is assumed not to prevent subsequent sleep.

Compared with caffeine, modafinil has demonstrated less cardiovascular stimulation, and less interference with scheduled sleep. But it was also shown to be less effective than caffeine

As seen above, Jet Lag means very different things as a function of the time zone differences, the direction of the flight, the duration of the stay, the purpose of the stay, the seasons, the differences in longitude. One must also add the still largely unexplored individual differences

Thus, there is no way presently to universally suppress Jet Lag and its consequences. The best way to adjust nowadays is to break the issue down and to look for tailored solutions, especially taking into account the difference in time zones and flight directions. For each one, specific adjustment strategies can be proposed, and they will be more efficient and less harm-

Jet Lag is a phenomenon that is best explained by a mismatch between the circadian body clock and actual destination time. After fast (airplane) transportation to destination, the body clock remains set to departure schedules for a number of days that depend mostly on the

The circadian clock slowly adjusts to new schedules, thanks to external time-givers, especially

Several remedies have been tried to speed up or bypass this adaptation, from no-nonsense tricks to bright light and melatonin to sleeping pills and stimulants. But, all in all, these remedies still tackle the issue in an unsatisfactory way. The best manner to cope presently seems

the alternation of outside night and dark periods but also social meetings and meals.

to tailor the solutions to individual travels and demands.

of coffee.

*4.5.4. Modafinil*

excessive daytime sleepiness [45].

74 Circadian Rhythm - Cellular and Molecular Mechanisms

on the Stanford vigilance test [46].

**4.6. Tailoring remedies**

in sensitivity to it.

**5. Conclusions**

ful than universal ones [47].

amount of time zones crossed.

There is no conflict of interest.
