Posted by alan on January 21, 1999, at 23:18:51
In reply to Re: Meds, posted by Elizabeth on January 19, 1999, at 1:05:49
> > The pharmacology of Effexor is as I described. At low doses it blocks only serotonin reuptake. At medium to high doses it blocks both serotonin and norepinephrine and at very high doses it blocks dopamine as well as the other two. Stephen Stahl, MD PHD has written some very clear and concise articles and texts on the pharmacology of antidepressants and antipsychotics, if you are looking for a good reference.
> Okay, so it *doesn't* act as an MAOI. That's what I thought.
> I'm not so clear that the means whereby neurotransmitter concentrations are increased is irrelevant. There seem to be quite a few differences between MAOIs and mixed reuptake inhibitors, even though they would seem to have the same effects, if you just look at which neurotransmitter levels are affected.
To follow up: A drug that increases or decreases the total level of a neurotransmitter
may have quite different effects at diffferent subtypes of receptors for that neurotransmitter, the drug not being the neurotransmitter itself. And that too is gross oversimplification. Thus two drugs that increase the total level of one neurotransmitter may initiate very different cascades of effects downstream, creating very different activity levels of various neurons, and thereby different active circuits. Different effects can be expected. The brain is not a neurotransmitter soup ('H'mm, this needs a dash more of salt/dopamine.); the brain is, functionaally, a set of possible cicuits. The neurotransmitters work a complex set of switches. If I'm not just all connfused--a distinct possibility--this conceptualization may provide some clarity. The striking fact of great similarity of effect of different drugs acting on one system is what most impresses me; not the differences. I hope I'm making sense.
poster:alan
thread:2088
URL: http://www.dr-bob.org/babble/19990101/msgs/2571.html