Translated from our German original by AI. The German text was researched, written, and edited by the Psychedelia Foundation team and remains the authoritative version.
A recent systematic review reaches a cautious conclusion about the use of kratom (Mitragyna speciosa) against pain. Preclinical studies do consistently show pain-inhibiting effects of kratom and its alkaloids, but the human data available so far are not sufficient to demonstrate clinical efficacy. The review appeared in May 2026 in Phytomedicine Plus.
For the analysis, the researchers evaluated 44 studies, among them 28 preclinical and 16 human studies. In animal and other experimental models, kratom and its alkaloids showed dose-dependent antinociceptive and anti-inflammatory effects. Among the possible mechanisms discussed are effects at the μ-opioid receptor.
The clinical evidence, by contrast, is considerably thinner. In studies with mitragynine, no significant changes in pain threshold or pain tolerance were found. A kratom decoction moderately increased pain tolerance in healthy participants in an experimental pain test. That does not allow any conclusion about efficacy in chronic pain or in pain requiring clinical treatment.
The safety data are limited as well. Single low to moderate doses of mitragynine or kratom were on the whole well tolerated in the human studies reviewed; the side effects observed were mostly mild and temporary. This says nothing about the safety of longer-term or high-dose use. The authors point in particular to possible dependence and withdrawal symptoms with chronic or high-dose use.
The review thus draws a nuanced picture: kratom has a pain-inhibiting potential that is well documented in preclinical models, but a clinically relevant analgesic benefit in humans has not been demonstrated so far. In the authors’ view, controlled clinical trials are needed to assess efficacy and long-term safety more reliably.
