Posted by CamW on April 13, 2008, at 11:44:00
In reply to Message to posters...., posted by LiveandThink on April 13, 2008, at 0:13:40
LiveandThink - There "may" be an interaction between melatonin and Prozac (fluoxetine). Some evidence comes from animal studies, but how these relate to humans is still unresolved (as far as I know; I been out of the loop for a couple years. In animal studies, melatonin does decrease levels of fluoxetine, but the significance of this is in question.
A molecule related to fluoxetine, fluvoxamine (Luvox) naturally increases blood levels of melatonin. When fluvoxamine and melatonin are taken at the same time, blood levels of melatonin are significantly higher than if the melatonin were taken by itself. The result of this interaction is an increase in melatonin side effects (eg. headache, nausea, and increased drowsiness). Whether this results in any real danger (in most cases) is doubtful, although the literature does not recommend taking melatonin and fluvoxamine together.
The drug interaction between fluvoxamine and melatonin is probably due to fluvoxamine's inhibition of the cytochrome P450 system (CYP); specifically CYP1A2 and CYP2C9 isoenzymes.
Since fluoxetine (Proac) is an even more potent inhibitor of the CYP2C9 isoenzyme (and also inhibits CYP1A2), and since melatonin is, at least partially, metabolized by CYP2C9, it might be prudent to use melatonin with caution (if at all) with fluoxetine (in my opinion).
I do remember a paper a couple of years back where the author(s) suggested using fluoxetine and melatonin together for the management of neuropathic pain. I have not heard if anyone has done a study of this therapy, and, from my experiences with neuropathic pain, I doubt that this is a very efficacious combination.
I hope that this is of some help. - Cam
poster:CamW
thread:823001
URL: http://www.dr-bob.org/babble/20080412/msgs/823044.html