I'm sorry to contradict so many that have said otherwise, but yes you certainly can build a tolerance to DMT.
The tolerance build up and diminishing process for DMT exhibits similar patterns to that of LSD and other psychedelics but on a different scale and length of time. The reason that it often does not seem like the tolerance has built up is because tolerance diminishes rather quickly. I can say this with absolute certainty because I have experienced it consistently throughout several repeated experiments with my personal Spice Journeys.
As I have discovered, if I go about 6 months without any Spice Journeys to cleans my system, then go through my Spice Journey, when I reach about 6 to 8 hours of repeated smoking of the freebases, which can be anywhere between 30 and 50 doses, there is a point in which tolerance levels are so high that it does not matter at all how big of a dose I smoke. It does nothing beyond irritate the throat and lungs. At this point I have pressed so far, in the name of scientific curiosity, as to vaporize 100mg doses back to back with only enough time between each to catch my breath. The maximum number of 100mg doses that I have ever vaporized back to back, one after the other, after having reached this "brick wall" was 12. (Yes this is 12 consecutive 100mg doses vaporized. It is not a typo, and it is not an exaggeration or embellishment.) In absolutely no circumstance was I ever able to get any DMT effects from vaporizing any amount of DMT once I hit this "brick wall of absolute tolerance and immunity", even when this experiment was repeated. The only thing that was achieved by repeated vaporization of DMT immediately after reaching the "brick wall" was lightheadedness and a slight head rush from all of the inhaling, a sore throat and lungs, some restricted breathing for a while afterwards, and a nasty headache.
Through further experimentation additional discoveries were made. After reaching that "brick wall" the absolute tolerance begins to diminish. Once that "brick wall of absolute tolerance" was reached, I found that if I wait 30 minutes to an hour, then vaporize 100mg, I can at least feel a little something. Usually it is not much more than a slight rush or load that washes over the body but occasionally I would get about 5 or 10 seconds of visuals. Additionally, if I wait longer, then I am actually able to achieve a good breakthrough somewhere between 2 and 5 hours after the "brick wall" was reached. However, a second dosing within the hour is a gamble, and a third dosing very rarely results in a breakthrough, and sometimes doesn't even result in any visuals.
Furthermore, when I wait a day or two after having reached that "brick wall" before I go on another Journey, then, within 2 or 3 hours (approximately between 10 and 20 doses), the entire Journey comes to an abrupt end as I hit the "brick wall" again. Additionally, if instead I wait a week or two then I am able to go 4 to 6 hours before reaching the "brick wall".
I have also learned that there is a pattern to how long it takes to reach the "brick wall" and it depends on how often I take my Spice Journeys. If I take a Spice Journey regularly once per week then the Journeys will balance out and they will last about 4 hours. If I take regular Journeys once every two weeks then the Journeys last at least 4 hours with most being able get to the 5 hour mark and sometimes as much as 6 hours. If I take regular Spice Journeys once a month then I don't have a problem reaching at least 6 hours or more. But, it usually takes at least 4 months before I can reach 7 or 8 hours again. Finally, the longest Journey that I have ever been able to achieve was about 9 hours but it was only after about an 8 month cleansing and it was assisted by pharmahuasca in addition to the usual fumahuasca.
This paragraph is just to make some clarifications regarding these experiments and my Spice Journeys. First of all, my Spice Journeys are not practiced in the typical manner. Generally, when I begin a Journey it is my intent to go very deep into hyperspace and remain well beyond the breakthrough barrier for as long as possible in the next 5 hours or so. Additionally, by the time I recognized the tolerance build up and decided to experiment with it, I was already beyond the point that I quit worrying about measuring my doses. The only time I measured doses was when I was specifically trying to discover how much DMT it would take after having reached the "brick wall". What I can say is that over the length of time that my Journey lasts, the doses start out smaller and tend to get larger and larger until I reach the point that I can't fit any more in my lungs. At that point the doses just occur more often until I reach the "brick wall". Additionally, I will also note that my Spice Journeys during these experiments were initially and primarily done with fumahuasca using a freebase extracted from rue, however, similar results were achieved with strait white DMT as well, however, the time lengths of the Journeys were usually a little shorter. Finally, I will say that since then I have begun using a combination of fumahuasca and pharmahuasca. I have not taken notes the way I did when I was more actively 'experimenting' but so far I still see similar results but with the addition of pharma it does seem to make it easier to stay in breakthrough hyperspace during the time periods of the Spice Journeys.
Now to bring this to a close I will leave you with a short description of the "brick wall of absolute tolerance and immunity". When I reach the "brick wall" I know it immediately. It is really kind of weird. We all know how quickly the climb can occur when smoking pure DMT. The "brick wall" is like the opposite of that effect. I have almost always been in a very deep and intense breakthrough when, all of a sudden, I just drop out and within 30 to 45 seconds I go from complete breakthrough (out of body, beyond ego death, existing beyond the universe) to completely sober and strait even able to walk a strait line heal to toe, toe to heal forwards and backwards. The one good thing is that the "afterglow" still remains.
Final Disclaimer: In absolutely no way am I promoting or encouraging anyone to experiment with DMT, fumahuasca, or pharmahuasca, or any combination thereof, in the same or similar manner or method of which I tend to practice. I recognize that the majority of people who experiment with these substances do not use them in the same way that I do. These are very powerful substances with a significant amount of variance in how they can affect different people. What is comfortable and enjoying for one person may be unexciting and boring for another person and what one person may find to be the perfect dose resulting in the ultimate most beautiful experience may very well scare the holy hell out of another person. So please, if you are to dose these substances, experiment wisely and cautiously to find what is right for you and allow others to do the same. And when another person prefers a different dose, then neither condemn, nor admire them for that. Please except that we are all different and sometimes we prefer different things.
