A long-awaited kratom clinical study conducted by the U.S. Food and Drug Administration (FDA) has been published in the Journal of Clinical Psychopharmacology. The pilot study (defined as “a preliminary investigation designed to test the feasibility and design of a larger, more comprehensive study”) involved healthy adult participants who were administered an ascending dose of plain leaf kratom in capsules from a single source to be consumed in a five-minute period. There were five cohorts with eight participants each, for a total of 40 participants. Six of the participants per cohort received kratom, and 2 received a placebo.
According to the abstract:
“The starting dose was 1 g and doses of 3, 8, 10, and 12 g were administered after safety reviews after each dose. After dosing, pupillometry and assessments of subjective effects were performed, and blood samples were collected. Safety assessments included adverse events (AE) monitoring, laboratory tests, vital signs, ECG assessments, physical examination findings, and assessment of suicidality.”
No serious adverse events were reported, though as expected, nausea resulted in the atypical higher doses. Most regular consumers of plain leaf kratom do not consume 8, 10, or 12 grams in a short, five-minute period of time.
According to the study, the 12 g dose also “produced increases on several subjective measures including ratings of ‘drug liking.'”
The lead contributor, FDA scientist Chad Reissig, first announced this study via livestream at the Third Scientific Kratom Symposium held at the University of Florida, Lake Nona, in 2024. A contributor to Kratom Science was in attendance along with scientists from around the world, legal experts, and kratom industry representatives.
Dr. Reissig explained that the broader study would start at the end of 2024 and results would be published approximately two years later (end of 2026). The broader study is a Human Abuse Potential (HAP) study on kratom. This is also a randomized, placebo-controlled clinical trial that the FDA uses to determine drug scheduling and requires for New Drug Applications (NDAs).
FDA has been criticized by the American Kratom Association (AKA) and other kratom advocates for leaving outdated information about the dangers of kratom on its official website, prompting local and state kratom prohibitions. In 2025, the FDA announced that it is recommending the Drug Enforcement Administration (DEA) place 7-hydroxymitragynine, but not plain leaf kratom, on its list of Schedule I controlled substances. This signals a shift in policy since 2016, when the FDA made the same recommendation about all kratom. The DEA decided to make kratom Schedule I, but reversed its decision after a grassroots mass movement opposed it.
The entire preliminary single ascending dose study is currently behind a paywall, and therefore blood test and other results are not yet freely available to the public.
Study Citation
Reissig, C. J., Chen, L., Nallani, S. C., Hawkins, E. G., Galati, S., Bonson, K., Kanumuri, S. R. R., McCurdy, C. R., Sharma, A., Setnik, B., Milovan, D., Kelsh, D., & Chiapperino, D. (2026). A Pilot, Dose-Finding, Pharmacodynamic and Pharmacokinetic Study of Orally Administered Botanical Kratom. Journal of clinical psychopharmacology, 10.1097/JCP.0000000000002158. Advance online publication. https://doi.org/10.1097/JCP.0000000000002158
My thoughts, and i forgot to include the sleep benefits. 100% have helped me with deep and continuous sleep. I used to not be able to sleep, and then restless legs syndrome would just punish me all night…Now I can;t even imagine, it took me this long to be cured by this magical God gifted herb/leaf.
This is 100 percent true. Please stop taking away any GOD GIFTED natural remedies for humankind.
I will keep it short and simple.
1- I cannot smoke or use marijuana. So as a substitute, people with severe anxiety can have an alternative. KRATOM calms the nerves.
2- I am a OIF/OEF deployed USMC Marine Veteran, with all the trauma I have been through. This. Medicine has helped me with my anxiety, PTSD, DEPRESSION, and some more disorders, to the point where I can finally be functional and have some hope to get out of bed and be happy and be able to or at least try to have a semi okay life.
3- Yes, I qualify for medical marijuana, but. It does not help me. The medical /marijuana effects are severe or too much for me. Kratom being a non-intense Natural plant has ANTI-DEPRESSANT, calming and anti-anxiety type effects on me, so I am able to continue having a job.
4- Kratom has SAVED MY LIFE. Due to PTSD and DEPRESSION, I had become a daily hard liquor drinker on the edge of going into hard drugs. I am diagnosed by severe fatty liver and was told that I wouldn’t live long due to ALCOHOL;s negative effects on my body.
WITH KRATOM I AM 1 YEAR 100% SOBER FOM ALCOHOL. With Kratom, I was able to quit ALCOHOL and never look back.
5- If the issue is that people are overdosing or minors are getting a hold of it, then we have a distribution or Checking ID problem and we need to solve that issue; not just over-react and restrict the medicine (which it acts like) for an entire class of depressed population.
6- My thoughts, and i forgot to include the sleep benefits. 100% have helped me with deep and continuous sleep. I used to not be able to sleep, and then restless legs syndrome would just punish me all night…Now I can;t even imagine, it took me this long to be cured by this magical God gifted herb/leaf.
** We need to properly educate young population and control the distribution. 100% just like ALCOHOL and Marijuana programs.
THE ANSWER TO KRATOM BEING AVAILABVLE IS NOT :YES or :NO.
The WIN-WIN SOLUTION IS A POLICY JUST LIKE ALCOHOL AND MARIJUANS DISTRIBUTION. PROPER DISTRIBUTION, LIKE ABC STORES NATIONWIDE AND EVEN TAXING IT TO HELP PEOPLE, WHO MAY NOT USE IT APPROPRIATELY.
PLEASE DO NOT PUNISH THE DEPRESSED PEOPLE.
I take 23 capsules at one time 5 days per week. I have Sleep Apnea and insomnia, Kratom gives me clean sustained energy for the day. It is a life changer, I’ve been taking it for 6 years now, I have stopped dosing for 30 days at a time before with No adverse reaction, just incredibly tired and I struggle with major depression and something happens when I take Kratom, I have more clarity of mind and feel much better when I take it, my synapses fire much better. My liver enzymes etc are fine with no other health concerns.