Ketamine has no affect on serotonin. And from what I've read about MXE, it doesn't either.
People should probably stop spreading these seratonin syndrome rumors.
DXM is an oddity and works completely different than other dissociatives.
I'm not saying you should go combine MXE with MDMA or something, I'm just saying seratonin syndrome is not a risk.
And ketamine and MDMA is not at all a dsngerous combo.
Ofcourse we should use caution when combining drugs, but let's not go around around spreading false information.
http://www.ncbi.nlm.nih.gov/pubmed/6460944
Ketamine inhibits serotonin uptake in vivo.
Martin LL, Bouchal RL, Smith DJ.
Abstract
Anesthetic (120 and 160 mg/kg. i.p.) and subanesthetic (80 mg/kg) doses of ketamine HCl were found to prevent completely the depletion of whole brain serotonin (5-HT) by p-chloramphetamine (PCA). Furthermore, ketamine HCl (160 mg/kg) completely blocked the depletion of 5-HT by PCA in every individual brain region studied (Midbrain-thalamus, hypothalamus, striatum, hippocampus and cortex). Administration of ketamine alone had no effect on brain 5-HT levels. Nialamide (a monoamine oxidase (MAO) inhibitor) and fluoxetine (a selective 5-HT uptake inhibitor) also prevented the depletion of 5-HT by PCA. However, of these three agents, only nialamide prevented the depletion of 5-HT by reserpine. These results suggest that ketamine blocks PCA-induced 5-HT depletion by inhibiting 5-HT uptake and not by inhibiting MAO. Ketamine only weakly affected either [3H]5-HT or [3H]spiroperidol binding to 5-HT1 and 5-HT2 receptors respectively even at concentrations as high as 1 mM. These data support the contention that the primary direct effect of ketamine on serotonergic systems is the blockade of 5-HT uptake and that blockade of 5-HT uptake may mediate some of the behavioral effects of ketamine, such as analgesia.
^ Studies suggest Ketamine is a Serotonin Reuptake Inhibitor like DXM, and I believe I read elsewhere that this was thought to be one of the few reasons for why it has great anti-depressant potential, though that I'm not 100% sure of so take my words with a pinch of salt.
(They also tell us that it's not a Serotonin Releaser. But combining an SRI with another SRI is dangerous, and MDMA itself has SRI action.)
That said, it's not a strong one, so in reality the combo is unlikely to be dangerous, unless maybe you were close to overdose levels of both drugs in the first place, particularly given how high the doses in the test were. However, given that I only really like to indulge with high doses of Ketamine, it just seems a risk not worth taking, however small the actual risk is.
Given the similarity in structure it's plausible to say MXE will have a similar effect, and given it hasn't been studied we can't say if the effect will be the same, weaker, stronger.. So it just seems very anti-harm reduction to tell people the combo would be safe just yet
If you're interested, another similar study talks about its effects on Dopamine and Norepinephrine too:
http://www.ncbi.nlm.nih.gov/pubmed/12963082 Interesting how Dopamine is only affected by one of the isomers.
Short version: Given how weak an SRI Ketamine is I really don't think the potential for Serotonin Syndrome is there, but isn't the best advice to never combine SRIs, no matter how weak they are?
