Kratom and Pain Tolerance: A Randomized, Placebo-Controlled, Double-Blind Study.
The only placebo-controlled kratom study involved 26 experienced users and a single dose for pain tolerance — does anything about my situation justify relying on evidence that thin?
Reasonable evidence with real limitations. how we score evidence
Kratom has never been approved by the FDA for any medical use and is not a lawful dietary supplement ingredient in the FDA's view; the agency has issued import alerts, warning letters, and repeated public warnings against its use.
The first randomized, placebo-controlled, double-blind human study of kratom — 26 Malaysian men with about 6 years of daily use — found cold-pressor pain tolerance roughly doubled one hour after a kratom decoction (11.2 to 24.9 seconds, p=0.02) with no change after placebo, and no withdrawal signs over 10-20 hours of abstinence. This tiny single-dose study in habituated users is essentially the entire controlled-trial evidence base for kratom; it says nothing about mental health outcomes, safety, or new users.
Worth asking
The only placebo-controlled kratom study involved 26 experienced users and a single dose for pain tolerance — does anything about my situation justify relying on evidence that thin?
Source
Kratom and Pain Tolerance: A Randomized, Placebo-Controlled, Double-Blind Study. — Vicknasingam B, Chooi WT, Rahim AA, et al. (2020)
Indexed peer-reviewed journal
How this was scored
- Study design
- Randomised controlled trial
- Funding
- Independently funded
- Published in
- Indexed peer-reviewed journal
- Sample size
- 26
- Preregistered
- No
- Conflicts disclosed
- No
- Independent of proponent
- Yes
- Retracted
- No
Read the full scoring rubric, including what it can't tell you.
Published August 19, 2026.
Questions
How strong is the evidence behind this?
Resolv rates this source "moderate evidence". Reasonable evidence with real limitations. It scores 68 out of 100 on our published rubric. The score is calculated from recorded facts about the source — study design, funding, publication venue, sample size, preregistration — not typed in by an editor.
What is the source for this?
Kratom and Pain Tolerance: A Randomized, Placebo-Controlled, Double-Blind Study. — Vicknasingam B, Chooi WT, Rahim AA, et al. (2020). Published in: Indexed peer-reviewed journal. The full source is linked on this page so you can read it yourself.
Who paid for this research, and does that matter?
Study design: Randomised controlled trial. Funding: Independently funded. The researchers were independent of whoever benefits from the result. Industry sponsorship is one of the most reliably measured biases in medicine, which is why funding carries real weight in the score rather than sitting in a footnote.
Is kratom, mitragyna speciosa, ketum, biak-biak, thang, kakuam FDA approved for this use?
No. Its current status is: Not FDA-evaluated for this use. Kratom has never been approved by the FDA for any medical use and is not a lawful dietary supplement ingredient in the FDA's view; the agency has issued import alerts, warning letters, and repeated public warnings against its use.
Is this medical advice?
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.