Twenty nine decoctions of Banisteriopsis caapi from four different sources and one specimen of B. caapi paste were analyzed for N,N-dimethyltryptamine (DMT), tetrahydroharmine (THH), harmaline and harmine. Other plants were also used in the preparation of these products, typically Psychotria viridis, which provides DMT. There were considerable variations in alkaloid profiles, both within and between sample sources. DMT was not detected in all samples. Additional THH may be formed from both harmine and harmaline during the preparation of these products. The alkaloid composition of one decoction sample did not change significantly after standing at room temperature for 80 days, but the initial acidic pH was neutralized by natural fermentation after 50 days.