Dextromethorphan is used for its antitussive properties in cough syrup.
Since its metabolized in the liver by the same cytochrome 2D6, DM and MDMA will compete for the active site.
Now I have no clue as to which binds more and is faster metabolized but Im sure that some DM will occupy the enzyme site, increasing the half-life of MDMA, to which extent is hard to predict.
was quite amazed by this find. Since I´m not sure yet how these substances have an effect on my mind (I mean: what path do the molecules follow once ingested, how are these molecules transported to the avtive centers, and what exactly binds where). I have the information somewhere. It is just a matter of retrieving and reading
The path is the same once ingested. Once in the blood it doesnt matter which salt you take. Its a matter of solubility and absorption rate. The salt is dissolved in your stomach, the freebase is absorbed more and more as the pH of the digestive tract increases. Now on an empty stomach, the stomach empties itself much faster since it doesnt need to digest food. So it happens quickly on an empty stomach.
Once ingested, it goes to the liver where is it metabolized to a great extent by first pass metabolism. Here's where I believe DM could be useful(taking it 15-30 minutes before E, to reduce first pass metabolism).
Then from your blood it crosses the Blood Brain Barrier(BBB) where it reaches its active site at serotonin neurons. Only the mdma freebase can cross the BBB, so no matter what salt used, it doesnt change a thing as far as the actual effect on your brain.
The difference between the 2 salts can only come from solubility and therefore absorption rate and maybe bioavailability.
For its absorption, the salt has to be dissolved. With a lower solubility, the absorption will be slower. If the molecule is absorbed at a specific part of the intestine, then the bioavailability could also be reduced. I dont think its the case here, so its probably just absorption rate due to solubility.
With a slower absorption rate, a smoother, longer lasting buzz since the peak concentration in blood is lower and the absorption longer.
What you describe really makes sense. I know HCl salt is fast around 15 minutes on en empty stomach for me. So maybe its just that the phosphate salt is less soluble under physiologic conditions then the hydrochloride salt.