5.3 Ayahuasca
There is one observational study investigating the effects of ayahuasca
on substance misuse and psychological functioning in 12 participants
with no specific psychiatric or SUD.99 The
intervention was a four-day retreat including two “ayahuasca
ceremonies” (50-100mL of ayahuasca) and various addiction-related
psychosocial intervention groups. As a major limitation, the diagnosis
regarding opioid use (i.e., whether or not participants had OUD)
entering the study was not reported; however, it is noted that some
participants were receiving methadone treatment. The primary substance
use measure was the Four-Week Substance Use Scale (4WSUS). Scores
reportedly decreased for all substances except for cannabis; however,
data on primary opioid use was not clearly reported. There was no
observed difference in opioid use among participants when comparing the
proportion who had used opioids at the baseline and the six-month
follow-up. However, results showed statistically significant
improvements in multiple psychological measures, including mindfulness,
empowerment, hopefulness, quality of life-meaning, and quality of life
outlook across the whole group — which is generally consistent with
prior research on ayahuasca.100 Other studies on
ayahuasca have also suggested its effects on decreasing substance use
and potentially mitigating other negative psychosocial effects of drug
use, which may deserve future attention.101 These
themes also appear in qualitative work in those using ayahuasca for
addiction-related issues in indigenous communities among whom SUD is
prevalent.102 At this time, however, there are no
currently registered ayahuasca trials for OUD or opioid dependence.