Is Bedtime Use of Kratom (Mitragyna Speciosa) a Sleep Aid or Disruptor? Examining Its Daily Effects and Individual Differences

Mun, Chung Jung
Timmons, Patricia
Panlilio, Leigh V.
Verrico, Christopher D.
Thomas, Ynhi T.
Zamarripa, C. Austin
Epstein, David H.
Smith, Kirsten E.

Edson College of Nursing and Health Innovation, Arizona State University
Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine
College of Health Solutions, Arizona State University
Real-World Assessment, Prediction, and Treatment Unit, National Institute on Drug Abuse Intramural Research Program, Baltimore, Maryland, United States
Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine
Henry J. N. Taub Department of Emergency Medicine, Baylor College of Medicine
Center for Innovations in Quality, Effectiveness, and Safety, Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas, United States

Jin H. Yoon served as action editor.

In the past 3 years, Kirsten E. Smith has served as a paid scientific advisor to the International Plant and Herbal Alliance and as an expert witness in legal cases involving kratom. The remaining authors have no conflicts of interest to declare. Research was supported by the National Institute on Drug Abuse Intramural Research Program of the National Institutes of Health and by National Institute on Drug Abuse (Grant DA055571) awarded to Kirsten E. Smith, and the National Institute of Neurological Disorders and Stroke (Grant R01NS129887) awarded to Chung Jung Mun.

Chung Jung Mun played a lead role in conceptualization, formal analysis, methodology, writing–original draft, and writing–review and editing. Patricia Timmons played a lead role in writing–review and editing and a supporting role in conceptualization and writing–original draft. Leigh V. Panlilio played a lead role in data curation and a supporting role in validation and writing–review and editing. Christopher D. Verrico played a supporting role in validation and writing–review and editing. Ynhi T. Thomas played a supporting role in validation and writing–review and editing. C. Austin Zamarripa played a supporting role in validation and writing–review and editing. David H. Epstein played a lead role in supervision and writing–review and editing and a supporting role in project administration, resources, and writing–original draft. Kirsten E. Smith played a lead role in funding acquisition, methodology, project administration, resources, and supervision and a supporting role in conceptualization, writing–original draft, and writing–review and editing.

Chung Jung Mun, Edson College of Nursing and Health Innovation, Arizona State University, Health North, Suite 301, 550 North 3rd Street, Phoenix, AZ 85004, United States [email protected]

Kirsten E. Smith, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 5510 Nathan Shock Drive, Baltimore, MD 21224, United States [email protected]

Received March 28, 2025

revised June 2, 2025

Accepted July 7, 2025

Experimental and Clinical Psychopharmacology 33(5):p 513-522, October 2025. | DOI: 10.1037/pha0000794

Kratom (Mitragyna speciosa) is a psychoactive botanical native to Southeast Asia increasingly used in the United States for various self-reported benefits, including sleep improvement. However, empirical evidence concerning kratom’s effects on sleep is limited. Here, we examined the association between bedtime kratom use and self-reported sleep outcomes in naturalistic settings across consecutive days, while also exploring sex and chronic pain status as potential moderators. A secondary analysis was conducted using the data from a 15-day ecological momentary assessment study of 357 U.S. adults who reported regularly using kratom. Participants made daily reports of their bedtime kratom use and rated their sleep duration and quality. Linear mixed-effects models assessed associations between bedtime kratom use and sleep outcomes, with sex and chronic pain status as moderators, controlling for age. Bedtime kratom use occurred on 23.4% of days and was associated with modest increases in sleep duration (13 min) and perceived quality (5.93-point increase on a 0–100 scale). Female respondents reported greater improvements in sleep quality (but not duration) than male respondents. Participants with chronic pain reported greater improvements in sleep duration and quality compared to those without chronic pain. Bedtime kratom use is associated with modest sleep duration and quality improvements, particularly in adults with chronic pain, and better sleep quality in female respondents. These findings among experienced kratom consumers suggest the need for human laboratory studies in kratom-naïve participants to determine causality and underlying mechanisms, which could help inform clinical guidance and policy as kratom use continues to rise.