Insufflation is a viable ROA for methamphetamine.
I don't understand your logic; you say that insufflating a relatively pure water-soluble drug is worse than getting 40-50mg of m-amp along with 250mg or so inactive fillers and binders, most likely not soluble in water. Not only does it impede absorption of the drug, these things deposit themselves on your mucous membranes until enough mucous is produced to clear them. This is a big source of congestion and sinus infections.
People take their drugs in different ways. I always used to take my methamphetamine via insufflation, then moved on to oral admin, and then primarily rectal admin along with oral when I didn't have the privacy.
People are different, and we all change and are at different points in their lives.
I get your point. I will clarify my reasoning, even though i don't really want to talk about it:
manufacturing meth is done in a few different ways. There are nearly always left over by products, such as HCl, H2SO4, red phosphorus, lithium, NaOH… There is often some left over ephedrine HCl (highly corrosive in presence of water), which reacts with water to form H+ ions which corrode your nose further. This is in addition to requiring water to wash meth crystals out of your nose that don't dissolve, and the bleeding from the angular, sub-angular, granular shape of the particles (crushed properly, I hope) in your nose after snorting. The meth running down the back of your throat ends up in your mouth and rots your teeth.
Yaba (meth pills): are produced in Asian countries, often smoked on foil (which forms a blackish liquid), or snorted. The other powders/fillers/binders have the same effect as that of cutting up amphetamine base with glucose - it decreases the corrosion on the nasal passage. Somewhat similar to snorting an ecstasy pill over snorting pure MDMA.
Dexamphetamines (5mg pills): While you needs about 5 to feel anything from snorting these, the effect of fillers is similar to what i mentioned above, although there are more. I actually don't recommend snorting these at all. (nor smoking). Just take them orally. The particle nature is also bad for the nose.
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I could go on, but I hope you get my drift.
