Dr. Jos fights jetlag

"Viagra is the very first medicine that tackles the cause of jetlag."
 Dr. Jos: There's only one thing you can really do against jetlag: stay at home.

That's like saying: there's only one thing you can do against a hangover: don't drink alcohol.
Dr. Jos: Which is right of course, but I get your point. We'll going to travel by plane anyway, so the jetlags will keep on coming. And now you want to tell your readers how to solve this problem?

I'd love to!
Dr. Jos: First of all, I'd like to draw a clear line between travel fatigue and jetlag. Jetlag is a syndrome that occurs when you're travelling by plane to a different time zone. But you don't have to cross timelines to feel like shit. If you fly from Belgium to South-Africa, you won't have jetlag, but you'll feel tired and weak anyway. That's travel fatigue, the result of ten hours of imprisonment in an airplane filled with stale air, no movement, crap food and Heineken instead of trappist ale. You'll also get travel fatigue from long drives by car. Jetlag is something entirely different. Jetlag is what you get when you mess with your biological clock.

Ah, that clock does exist?
Dr. Jos: Absolutely! The biological clock is in the hypothalamus, in the brain, and it's predominantly influenced by daylight. Parallel with the cycle of light and dark, the pineal gland releases melatonin. That's a hormone that regulates sleep activity, for instance by slightly lowering body temperature at night, decreasing the degree of activity... In short, melatonin times the circadian rhythm. Now, the biological clock is a tough one. Even if you isolate people from time and space, their biological clock will keep on ticking. Light is the most important factor, because of a direct link between the eye and the hypothalamus. However, blind people also have a functioning biological clock, so the existence of extra-ocular photo receptors is suspected. Some claim these are located in the knee pits, but that's controversial. Who knows, we might even have eyes on our behinds! (roars with laughter)

Okay, so our biological clock is ticking. What happens if you mess with it?
Dr. Jos: The biological clock doesn't like to be influenced. It's resistant to phase-shifting. I'll visualize it for you: you can't just turn the dials of your biological clock to a different time zone. You'll have problems sleeping for a few days and nights, with some other discomfort on top. Your body releases melatonin when you're supposed to sleep at home, while on your travel destination, it's daytime. And vice versa: in the middle of the night, you'll wake up in your hotel room. That can make you feel really crappy.

Can't it be fixed with medication?
Dr. Jos: (shrugs and takes a sip from his trappist) What do I answer now, yes or no? Yes, but that would be pure symptom treatment. No, because you can't force the biological clock. You could take sleeping pills in the first two or three days after you arrive at your destination. Or you could take additional melatonin when you go to sleep. But melatonin is a problematic molecule. There's no patent on it, so the pharmaceutical industry can't make any money selling it. As a result of this, no research is being done on the long term health effects of taking melatonin. There's a total lack of safety tests. And who jumps in? Alternative medicine, and now you'll even see melatonin sold as a food supplement. You can order it on the Internet, in doses that can't be controlled in any way. Unbelievable!

Let's just lay off the pills then?
Dr. Jos: Well... (grins) after a lot of research, I've found a decent alternative. There's a safe medicine that's been very thoroughly tested and researched. Hamster experiments show that it facilitates adjustment of the biological clock. It's a cyclical GMP-phosphodiesterase-inhibitor called sildenafil. You'll know it better by its brand name: Viagra.

(stunned) Are you serious?!
Dr. Jos: (raises his glass) What can I say? The lab results speak for themselves. Viagra is the first medicine that tackles the cause of jetlag, instead of the symptoms. Works just as well for women, by the way. Between you and me: I think the membership of the Mile High Club will, eh, firmly erect after this revelation (grins broadly and empties his trappist)




Dr. Jos recommends these relevant papers:
Agostino e.a., Sildenafil accelerates reentrainment of circadian rhythms after advancing light schedules, PNAS., jun. 2007
Waterhouse e.a., Jet lag: trends and coping strategies, Lancet., mrt. 2007
Sack e.a., Circadian rhythm sleep disorders: Part I, basic principles, shits work and jet lag disorders, Sleep., nov. 2007
Buscemi e.a., Efficacy and safety of exogenous melatonin for secondary sleep disorders and sleep disorders accompanying sleep restriction: meta-analysis, BMJ., feb. 2006
Herxheimer e.a., The prevention and treatment of jet lag, BMJ., feb. 2003
Srinivasan e.a., Jet lag: therapeutic use of melatonin and possible application of melatonin analogs, Travel-Med-Infect-Dis., jan-mrt. 2008
Waterhouse e.a., Further assessments of the relationship between jet lag and some of its symptoms, Chronobiol-Int., 2005
Filipski e.a., Effects of chronic jet lag on tumor progression in mice, Cancer-Res., nov. 2004
Waterhouse e.a., Identifying some determinants of jet lag and its symptoms: a study of athletes and other travellers, Br-J-Sports-Med., feb. 2002
Cho e.a., Chronic jet lag produces cognitive deficits, J-Neurosci., mrt. 2000
Reilly e.a., Travel fatigue and jet-lag, J-Sports-Sci., jun. 1997