Nardil, Marplan, Eutony, Parnate and others of a then common family of antidepressant drugs. The presence of a DMT-generating enzyme in human brain was particularly exciting because we knew from the work of Harvard botanist, Richard Shultes and others, that DMT and the monoamine oxidase inhibitor, beta carboline, are combined in a mixture of the leaves of a shrub and the bark of a vine, both Amazonian plants, used together by the shaman of Peru, Colombia and Ecuador for thousands of years to evoke mystical experiences in themselves. In their state of chemically-facilitated, spiritual transformation, they were better able to engage in healing and divination of others. More recently this and other similarly acting biochemicals have been called entheogenic, “connecting to the sacred within.” Consistent with our neurochemical findings in human brain, the shamanic concoction, called by many names including ayahuasca and yage, combined the DMT containing plant, Psychotria viridis, with an extract of a vine with the powerful monoamine oxidase inhibitor properties of the beta carbolines found in Banisteriospsis caapi. In 1975, working with a graduate student, Louise Hsu, we found that the mammalian brain could also synthesize beta carbolines. This family of compounds from the vine protects the tryptamine substrate as well as DMT from metabolic degradation such that it could circulate in the blood long enough after oral ingestion for enough to cross the blood brain barrier to induced prolonged and dramatic alterations in perceptions, feelings and thoughts. In addition, the carbolines of the Benisteriospsis component extended the time of action of DMT beyond the 15-30 minutes of effect of DMT when injected alone in human subjects. We found it fascinating that the human brain made combinations of DMT and beta carbolines similar to the blend that indigenous shamamic chemists discovered as an entheogenic from plant sources. Ralph Metzner, in the introduction to his 1999 colle