Posted by sowhysosad on September 15, 2009, at 21:03:29
In reply to Re: How did Prozac cause my permanent Anhedonia, posted by metafunj on September 13, 2009, at 17:43:22
Fascinating theory.
> My theory is that taking prozac decreased your serotonin transporters. Stopping the drug does not restore this so you are left with lots of extra serotonin floating around.
So you're saying there are less transporters - an adaptive change under Prozac - so reuptake is inhibited, even when the drug is withdrawn?
> At the same time prozac caused an increase in dopamine transporters so now any dopamine your brain is making is being removed from the synapse before you can enjoy it.Why would there be an increase in dopamine transporters though? I know Prozac sensitizes D2 receptors in a region-specific manner, but I didn't know it affected the transporter cells.
Apparently the glut of serotonin in the synapse can also cause the dopamine transporters to reuptake serotonin, which can be released later and act as a false neurotransmitter. That would also fit with the theory.
> I found a study before, that I can't find now, which says that serotonin stays elevated even after drug cessation. Now your probably wondering why did you feel better on Prozac than off since in both cases you have increased serotonin. I think the reason you felt good on prozac is cuz prozac blocks the 5HT2C receptor and does something at the 5 HT2A receptor. This action causes increase in dopamine which makes you feel better and enjoy things.
>
> When you came off instead of being blocked by prozac, the 5 HT2A/C receptors became flooded with serotonin, due to decreased serotonin transporters. They are now being agonized by serotonin which is decreasing dopamine in the prefrontal cortex, which probably is contributing to anhedonia as well as cognitive problems.Makes a lot of sense - removing the 5-HT2C antagonism would cause a drop in dopamine release.
poster:sowhysosad
thread:914929
URL: http://www.dr-bob.org/babble/neuro/20090701/msgs/917301.html