If this was all there was to it, they would act as buffers, and when hit with a gassing they would all be in their acid state, or with xs base, they would all be in their base state...and the weaker base sudo or ephedrine couldn't compete with the strong base NaOH for spots on the polymer, or when gassed, the HCl should preferentially be absorbed over weak acid sudo HCl. In any case, an excess should overwhelm its buffer unless there is something more sinister involved...
I would like to add a further observation to the already excellent physical properties listed on this thread...
When the new pills are extracted after clean up and then gassed, the precipitate and left over solvent(toluene) are more unmanageable than I have ever seen. Rather than filter,
if the gassed toluene is then extracted into water, and after separating the toluene the water is based, crystals of sudo don't appear with Na2CO3 as basifier.
The best methods are always the simple ones. Chromatography will never be teachable to the masses. For this to remain a people's art, a simple and effective method of knocking out all the new adds must be pursued. I'm putting my bets on superheated steam. Regular steam distillation of ephedrine is borderline workable, and with sudo it just sucks. I'll bet steam hotter than it wants to be will carry the product out without wondering if the product in the pills is Orange Gak 1,2 or 3 or Eudrashit...and I'll bet it can be done on a stove top.