Posted by King Vultan on October 15, 2004, at 14:26:52
In reply to Re: anhedonia sucks, posted by jboud24 on October 15, 2004, at 11:43:56
> Who else has heard that Deprenyl is more dopamiergic than Parnate. I dont understand that when Parnate is supposed to actually cause the release of dopamine as a part of its actions in addition to MAO-B inhibition. I also read somewhere that Parnate is reversible in its actions. Can anyone verify that? In the PDR it says irreversible, but I have read in other places on the net, including babble, that it is actually reversible.
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> These are important issues for me since I have to go see my pdoc in a little under 2 weeks and I'll be asking for an MAOI.
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> Thanks,
> JustinSelegiline generates amphetamine and methamphetamine metabolites on its first pass hepatic metabolism. At lower dosages, it also selectively inhibits only MAO-B (it is irreversible, however). These abilities are why it has utility in Parkinson's Disease, which is caused by a loss of dopamine neurons, and it is classified as an anti-Parkinson med, not as an antidepressant.
Parnate OTOH has a very similar chemical formula and structure to that of amphetamine but only has a fraction of the stimulation ability on a mg by mg basis. The idea behind developing Parnate (tranylcypromine) way back when was to try to come up with a stimulant with less abuse potential than amphetamine. In this, they were successful, and the drug also revealed itself to be a very potent MAO inhibitor.
The selegiline metabolites are likely far more dopaminergic in practice; although, of these two drugs, I have only tried Parnate. I have also seen Parnate referred to as "reversible" or "partially reversible" but don't know what the basis is for referring to it in that manner. AFAIK, for all practical purposes, it is irreversible, and studies and anecdotal experience have shown that it also has the greatest tendency of any of the MAOIs to increase blood pressure when consuming foods containing tyramine.
Todd
poster:King Vultan
thread:403148
URL: http://www.dr-bob.org/babble/20041012/msgs/403422.html