The tribes drink a brew called ayahuasca. Ayahuasca, while it contains N,N-DMT, provides a much different experience than just vaporizing the DMT.
If you were to eat DMT by itself, it would be destroyed by the enzyme monoamine oxidase (MAO) in your stomach before it could take effect. To counteract this, people make a drink that contains both DMT and a monoamine oxidase inhibitor (MAOI). The MAOI inhibits the MAO in your stomach, allowing the DMT to be absorbed in your digestive tract. This provides for a much longer and (usually) smoother experience than a 10 minute vaporized DMT trip.
Last edited: Feb 19, 2015