Monkeys Tripping Out On Ayahuasca May Have Stumbled Upon An Effective Treatment For Depression


Current depression treatments don’t work for everyone (10 to 30 percent of depressed people are treatment resistant), which is why some researchers are looking into novel treatments like psychedelics. Now another psychedelic (ayahuasca) has been studied on common marmosets.

Ayahuasca is a powerful entheogen from the Amazon Basin. It’s a traditional brew containing two main ingredients: Psychotria viridis (a shrub containing DMT) and Banisteriopsis caapi (a vine containing three monoamine oxidase inhibitors, which prevent the DMT from breaking down in the digestive tract so that the ingested DMT will have psychedelic effects). Previous studies like this one and this one have suggested positive effects of ayahuasca, and studies have suggested it’s safe and non-addictive. A previous depression study demonstrated anti-depressant effects after only one dose. The new study has similar findings.

Nicole Galvão-Coelho and her team at the Federal University of Rio Grande do Norte in Brazil induced depression in common marmosets (Callithrix jacchus) by isolating them from other monkeys for eight weeks, but allowing them to hear and smell their fellow marmosets. They monitored the monkeys’ stressed-out behaviors (scratching, oversleeping, loss of appetite) and their levels of stress hormone cortisol.

24 hours after taking one dose of ayahuasca, the monkeys’ cortisol levels returned to the baseline and stressed-out behaviors decreased. Those positive effects lasted for 14 days. The researchers have already done a similar study with the common prescription drug Nortriptyline (a tricyclic antidepressant). The ayahuasca worked better, and faster, than Nortriptyline.

We need to point out a couple of caveats, however. The sample size was extremely small; only 15 marmosets tripped out on ayahuasca. Also, since ayahuasca contains three different monoamine oxidase inhibitors (MAOIs), this treatment could pose severe drug interactions for people already taking any of the numerous drugs which shouldn’t be taken with an MAOI, and that includes many common antidepressant medications.

The study is available on bioRxiv. No word on whether the tripping monkeys got any crazy ideas about stealing a bus.

(Via D-brief, NCBI, ResearchGate, Science Daily, Wiley, ScienceDirect, Journal of Clinical Psychopharmacology, and bioRxiv)