Posted by BrittPark on January 22, 2003, at 11:11:49
In reply to Re: opiates and major depression , posted by djmmm on January 22, 2003, at 8:42:35
> For what it's worth, tramadol's major pharmalogical effects are mediated through serotonin and norepinephrine reuptake. It only has minor effects on the opioid system. It is very similar to Effexor.
IIRC, tramadol's analgesic effect is about 50/50 opioid/catecholamine. In animal studies naloxone reverses about 50% of its analgesic effect.
Tramadol itself binds very poorly to opiate receptors but it 0-desmethyl metabolite binds much more strongly, though still relatively weekly.Now as to its mechanism as an AD it may well be NE/5-HT that's the key. But I'm betting that it is also the opiate receptor activity.
Cheers,
Britt
poster:BrittPark
thread:81414
URL: http://www.dr-bob.org/babble/20030119/msgs/137039.html