DwayneHoover
Bluelighter
Still, I'm really uncertain how much adding a little more ascorbic acid (vit C) in the form of a vitamin C pill (which was definitely the sentiment of the question) to the already low pH HCl environment of the stomach is going to slow the absorption of anything in a way that is reliably noticeable subjectively when it comes to tripping..
Your stomach is not constantly awash in a pool of acid. That would (1) be wasteful, as acids are very energy intensive to produce, and (2) it could be harmful to the stomach without the presence of something to digest. Endogenous acid is released ONLY when food is detected either by the mouth (taste, chewing, salivation) or directly by the stomach. So taking an amphetamine or a 2C or a -drone or anything alse based on phenethylamine ring on an empty stomach with either acidic or basic substances CAN AND DOES affect the drug's pharmacodynamics.
See the medical references I posted. This is not some crazy theory I just dreamt up. It happens enough for pharmacies to put little labels on oral amphetamines about drinking juice with them, OK? Plus I have experienced it, so have many others. It may not seem obvious to you but it is an established medical fact.

