Posted by saturn on April 30, 2006, at 17:08:23
In reply to Re: provigil vs caffeine » saturn, posted by zeugma on April 29, 2006, at 13:33:55
> Provigil and caffeine interact in a way different from that of say ritalin and caffeine, and I'm beginning to figure out why.
>
> Caffeine works by blocking adenosine receptors, and adenosine is a neurotransmitter that is part of the homeostatic sleep drive,i.e., the longer awake you are, the more adenosine accumulates. So caffeine blocks this process and lets you stay awake more easily.
>
> Provigil works in something of the same way. But since the brain is massively parallel, the system it works on is very different though functionally similar in some respects. It inhibits the sleep-promoting drive from the preoptic area of the hypothalamus, which is a very restricted area compared to the adenosinergic system which is diffuse. But both drugs block a sleep-promoting drive, so the two drugs definitely have more potential for interaction than Ritalin and caffeine, which is not to say that Provigil and caffeine necessarily amplify each other's effect, or subjectively feel similar at all. The effect is more subtle than that.
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> If, say, I have a large coffee on the way home from work, instead of a small coffee (large coffee approx. 30-40% larger) it can keep me up too late whereas the small coffee will have a negligible effect and not influence sleep time at all. On Ritalin, I could have had three large cups on the way home and it would not have made a difference beyond the usual, small effect caffeine has on wakefulness and alertness for me.Thanks for all that info. I always vaguely knew that adenosine was related to caffeine's effects, but you really clarified it for me.
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> But really, when i am in a stupor, like now, no drug makes a difference (end-of-the-week collapse).I know all to well what you mean ;)
sat
poster:saturn
thread:637606
URL: http://www.dr-bob.org/babble/20060429/msgs/638482.html