The effects of the medicine last between four and six hours for most people, while a ceremony can go up to six or nine hours, depending on the shaman. This might also depend on certain criteria in each individual, such as weight, height, health status, and one's tolerance and previous experience with taking ayahuasca. It should be noted that when used for personal transformation, spiritual development, or emotional, mental or spiritual healing, the longer-lasting effects of ayahuasca become deeply individualised. Many people often refer to a post-ceremony "afterglow" that can last for as long as up to 8 weeks after the experience.
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