You all know you can boil San Pedro tea down until it's thick, then spread it on a cookie sheet and dry it with a fan, right? Scrape the goo up and roll into little pill balls with some sugar, and you don't have to taste it. It's way less plant matter than encapsulated dry powdered cactus.
Will it still cause nausea? Absolutely. Pure mescaline causes nausea. But at least you dint have to drink bitter snot.
Please source your cactus domestically - I just learned that "sustainable" San Pedro is on track to be extinct in the wild in much of its native range due to commercial harvesting.
And OP, mescaline is gentle. If stronger psychedelics can't break through, I don't think it's likely to either.