ABOUT THIS EPISODE
In this episode
- Dr. Ryan Vandrey on what cannabis research could — and could not — support in 2020
- Why THC and CBD should not be treated as interchangeable
- Research on THC as a sleep aid going back to the late 1960s and 1970s
- THC and sleep-onset latency
- Why evidence for CBD as a sleep aid was much weaker
- REM sleep, slow-wave sleep and inconsistent sleep-architecture findings
- Why most early studies did not actually involve patients with diagnosed sleep disorders
- Tolerance, dependence and cannabis withdrawal
- Why withdrawal insomnia can be mistaken for proof that cannabis is necessary for sleep
- Vivid dreams and REM rebound after stopping heavy cannabis use
- PTSD, nightmares and the limits of the early evidence
- Why route of administration, THC/CBD ratio, dose and formulation matter
- The problem of standardization and quality control in cannabis research
- Why “it worked for me” is meaningful but not universal evidence
- What 2025 randomized evidence says about cannabinoids and subjective sleep quality
- Why CBD-only interventions still have not demonstrated a clear sleep benefit
- What the 2025 sleep-architecture meta-analysis says about REM suppression
- A 2026 Ryan Vandrey co-authored trial in people with diagnosed insomnia
- Michael Grandner’s secret past as a college radio DJ
- Christopher Depner and Kenneth Wright’s metabolomic search for a blood marker of insufficient sleep
- Why one biomarker is probably not enough to measure sleep deprivation
- How that biomarker research had advanced by 2024
- Dr. Daniel Buysse, brief behavioral treatment for insomnia and “insomnia judo”
- Using sleep pressure as part of behavioral insomnia treatment
About Dr. Ryan Vandrey
Ryan Vandrey, PhD, is Professor of Psychiatry and Behavioral Sciences at the Johns Hopkins University School of Medicine and works with the Behavioral Pharmacology Research Unit and Cannabis Science Lab. His research includes cannabis dose and formulation, route of administration, pharmacokinetics, medicinal use, cannabis-drug interactions, cannabis product testing, cannabis withdrawal and Cannabis Use Disorder — including the effects of cannabis use and withdrawal on sleep.
About Dr. Michael Grandner
Michael Grandner, PhD, is a clinical psychologist and behavioral sleep medicine specialist at the University of Arizona. In this recurring segment, he joins Neil to translate new sleep research into something useful — and, occasionally, to reveal that he once had a radio voice of his own.
MENTIONED
Dr. Ryan Vandrey — Johns Hopkins Medicine
Vandrey’s current faculty profile and research interests.
Cannabinoid therapies in the management of sleep disorders
The 2020 systematic review co-authored by Vandrey examining the preclinical and clinical evidence for cannabinoids and sleep.
Read the 2020 systematic review
Interactions between disordered sleep, post-traumatic stress disorder, and substance use disorders
Vandrey and colleagues’ 2014 review of sleep, PTSD and substance use.
Read the PTSD, sleep and substance-use review
Effectiveness of cannabinoids on subjective sleep quality
The 2025 meta-analysis of six randomized trials and 1,077 participants, including separate analyses of CBD-only and non-CBD interventions.
Read the 2025 randomized-trial meta-analysis
Cannabis and sleep architecture: A systematic review and meta-analysis
The 2025 review of objective polysomnographic evidence, including REM sleep and withdrawal.
Read the sleep-architecture meta-analysis
Acute Effects of Oral Cannabinoids on Sleep and High-Density EEG in Insomnia
The 2026 pilot randomized trial in 20 adults with diagnosed insomnia, co-authored by Ryan Vandrey.
Cannabis and sleep disorders: What clinicians need to know
The American Academy of Sleep Medicine’s 2024 overview of the evidence and clinical cautions.
Developing preliminary blood metabolomics-based biomarkers of insufficient sleep in humans
The Christopher Depner / Kenneth Wright paper Michael discusses in his weekly science segment.
Read the 2020 metabolomics paper
Accurate detection of acute sleep deprivation using a metabolomic biomarker
A 2024 machine-learning study showing how far the biomarker idea had progressed after this episode.
Read the 2024 sleep-deprivation biomarker study
Efficacy of brief behavioral treatment for chronic insomnia in older adults
Daniel Buysse and colleagues’ randomized trial of the brief behavioral insomnia treatment behind Michael’s “insomnia judo” discussion.
Songs About Sleep — The 15 Best Of All Time
The Snooze Button list that Michael’s former-radio-DJ story sends Neil back to.
