Posted by Larry Hoover on February 11, 2009, at 8:08:50
In reply to Re: Bipolar and Melatonin - Ativan - Magesium Citrate, posted by Garnet71 on February 10, 2009, at 23:54:20
> If this was true, according to the cited research, then how would a doctor know if you had this problem?
Melatonin secretion can be measured, but it's not used diagnostically. If certain types of sleep dysregulation occur, it may be considered prudent to do a melatonin challenge. If melatonin supplementation reduces symptoms, then it's presumed that pineal secretion was insufficient.
One thing about melatonin supplementation. The dose-response is not linear, as it is with many drugs. In other words, increasing the dose does not mean you increase the effect. There is a region of dosing for which this is true, but above that region, the effect diminishes rapidly. The dose-response curve looks like an upside-down capital letter U, stretched out a little bit so that the sides have a bit of a slope.
If you're on the left of the curve, as you increase the dose, you increase the effect. In the middle of the curve, the effect flattens out. Increasing dose has no further effect. Above that, you get diminished response, right down to none whatsoever. In fact, too much melatonin will prevent sleep, because the receptors are saturated and the body simply ignores the inappropriate signal that represents.
The problem is that different people have different doses at which this pattern applies. I find that 0.3 mg/night works really well. Others I've spoken to say that they need 6-9 mg to have any effect at all. That's 20 or 30 times what I take. So, you have to start at a lower dose and work up, to see how you respond. If you start too high, you might blow yourself out of the water before you've even had a chance to respond to it.
I suspect the high inter-individual variability in dose/response is due to differences in liver function and permeability at the blood/brain barrier. But who knows.
Lar
poster:Larry Hoover
thread:878922
URL: http://www.dr-bob.org/babble/20090203/msgs/879413.html