Ayahuasca combines two plants: one provides a reversible MAOI that prevents GI breakdown of DMT from the other plant, allowing it to cross the blood-brain barrier.

“And what's really kind of curious is that there are, as I understand it, 10 to 20,000 plant species in the Amazon. And somehow, somebody- - Someone tried 'em all. - Combined these two plants together in certain proportionality and cooked this for five, 10 hours to the point where you cook out the dimethyltryptamine out of one of the plants and cook out the reversible monoamine oxidase inhibitor out of the other plant in such a way that the reversible monoamine oxidase inhibitor prevents the GI breakdown of the dimethyltryptamine in such a way that it's then allowed to cross the blood-brain barrier and get into the brain.”