no offense but, if your friend know so little of how to do it, and some quite basic stuff like 'synthetic vs extracted', maybe he shouldnt really be doing this!
just for the sake of information, though:
extracted and synthetic makes absolutely no difference, considering they are both 100% pure.. dmt is dmt is dmt.
second, Strassman (who if you dont know has been in the last years the only person to research dmt legally in the world) used a sterile solution of dmt fumarate as the injectable form.
again, I advise against doing, specially because the questions seem to imply your friend has very little knowledge about this..
If he decides to still go for it, be REALLY careful! make sure the spice is VERY VERY VERY pure, recrystalizing minimum 3 or 5 or 10 times, making SURE there is no residual solvent, using sterile solution, pure fumaric acid, etc etc.. Have someone else make the injection (you dont want to go to hyperspace so fast and then have the needle hanging in your arm and hurt yourself or whatever), someone that has experience with iv/im use (doctor preferably) and start with very low doses.
but again I say, dont do it.. want a strong experience? Smoke a big dose, or take it orally with maoi, or smoke it during a mushroom trip! (but in any case, be careful, whatever way you consume, pleaaaaase!)
