Every shaman has his or her own way how to conduct the Ayahuasca ritual. The only common thing is that the Ayahuasca brew is drunk.
It is common that the participants of the ceremony take only light lunch the day of the ritual. Then they fast for the rest of the day.
The effects duration is according to the strenght of the vine and the particular recipe of Ayahuasca. While some shamans prepare weak and short-lasting medicine (2 hours or so), there are shamans who like preparing very strong Ayahuasca and they may even drink it several times during the night (thus achieving duration of 10 hours). Usually the effects last 4-6 hours.
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