CBN (Cannabinol): What It Is, Sleep Claims and Evidence
CBN is a minor cannabinoid formed as THC breaks down. See what it is, what a 2026 human sleep trial and older research found, and how to read sleep claims.
Content last updated . This page has not been medically reviewed.
Overview and classification
CBN (cannabinol) is a minor cannabinoid. It is an oxidative by-product of THC, which means it forms as THC breaks down. [1] A review notes THCA-A slowly turns into THC in storage and can degrade further to CBN. [2] CBN is claimed to be a sleep aid; whether that is true in people is the main question below. [1]Evidence labels used on this page: promising but limited, mixed, preclinical (cells/animals only), insufficient evidence, marketing claim.
Where it comes from
CBN is described as a by-product that appears as THC and its acid break down, including during storage. [2] [1] This page does not describe how to make it. CBN is used in "isolate" products in the community. [3] Composition varies, and batch data should be checked. See CBD, CBG blends and CBN oils.Does CBN help sleep?
Marketing claim. CBN is marketed for sleep. The research is limited:| Evidence | Label | What it found |
|---|---|---|
| Review of human studies (2021) | insufficient evidence | A PubMed search screened the abstracts of 99 human studies. Most human work dated from the 1970s and 1980s with small samples. No clinical trials with validated sleep questionnaires or formal sleep recording (polysomnography) were found, so the reviewer concluded there is insufficient published evidence to support sleep claims. [4] The same review said evidence that CBN itself causes cannabis-like effects in humans is mixed. [4] |
| Rat study (2025) | preclinical (cells/animals only) | CBN increased total sleep time in rats, with a biphasic pattern (early sleep suppression, then increased sleep). [3] |
| Human trial in insomnia (2026) | mixed / promising but limited | Twenty adults with physician-diagnosed insomnia took a single oral study amount of 30 mg or 300 mg CBN, or placebo, in a crossover design. [1] The primary outcome, time awake after sleep onset on overnight polysomnography, did not change significantly. [1] The 300 mg amount increased one sleep stage (NREM-2), and other results were reported for sleep quality and time to fall asleep. [1] There were 247 mild-to-moderate adverse events across the study arms, and the authors called for larger, longer trials. [1] |
What this means: the best human trial so far was small, tested one night, and missed its main target. The 2021 review recommended that future trials use amounts significantly higher than those in the sleep products it looked at (typically up to 5 mg), so trial amounts do not map neatly onto what is sold. [4] These are study amounts, not recommendations. Proper evidence not found that CBN is an effective, safe sleep aid in everyday use. For the wider evidence, see cannabis and cannabinoids for sleep and cannabinoid products marketed for sleep. For non-cannabis sleep information, see how sleep works.
Risks, interactions and unknowns
The rat study found that CBN's main metabolite, 11-hydroxy-CBN, reached brain levels similar to CBN and was active at cannabinoid CB1 receptors with potency and efficacy comparable to THC. [3] This suggests an active metabolite may help explain the effects seen in animals, and whether it matters for next-day alertness or driving in people is not established by the sources read. The 2026 insomnia trial reported adverse events but its abstract does not break them down. [1] Sleepiness from any product can affect driving; see cannabis impairment and driving.Regulatory category (United States, read 2026-10-22)
The FDA says it has not approved a marketing application for cannabis for any disease or condition. [5] The 2018 Farm Bill hemp definition quoted by the FDA covers the plant's derivatives, cannabinoids, isomers and acids with a delta-9 THC concentration of not more than 0.3 percent on a dry weight basis; no CBN-specific rule was verified. [5] That definition is being amended to total THC, with portions delayed to December 11, 2026. [6] Other countries and states were not verified. Laws change, and this is not legal advice. See cannabis and CBD laws by country.Special groups
Proper evidence on CBN in pregnancy, breastfeeding, children, older adults, or people with heart, liver or mental health conditions was not found. That is not evidence of safety. People who take sedating medicines or other sleep aids should ask a pharmacist or prescriber; see medication interactions. Keep products away from children; in the US, call Poison Help at 1-800-222-1222 or 911 in an emergency.Frequently asked questions
What is CBN?
CBN (cannabinol) is a minor cannabinoid that forms as THC oxidizes. [1]
Does CBN make you sleepy?
In rats it increased total sleep time. [3] In people, evidence is limited: a 2021 review found insufficient evidence for sleep claims, and a small 2026 trial missed its main sleep outcome. [4] [1]
Is CBN psychoactive?
A review found evidence that CBN itself causes cannabis-like effects in humans is mixed. [4]
Is CBN approved as a medicine?
No CBN medicine was found. The FDA says it has not approved cannabis for any disease or condition. [5]
How does CBN differ from CBD?
They are different molecules; see CBD vs CBG and CBN.
References
- Lavender et al. Cannabinol for Acute Treatment of Insomnia Disorder in a Randomized Placebo-Controlled Crossover Trial. Journal of Sleep Research. 2026. PubMed abstract read 2026-10-22.
- Moreno-Sanz G. Can You Pass the Acid Test? Critical Review and Novel Therapeutic Perspectives of Delta-9-Tetrahydrocannabinolic Acid A. Cannabis and Cannabinoid Research. 2016. PubMed abstract read 2026-10-22.
- Arnold et al. A sleepy cannabis constituent: cannabinol and its active metabolite influence sleep architecture in rats. Neuropsychopharmacology. 2025. PubMed abstract read 2026-10-22.
- Corroon J. Cannabinol and Sleep: Separating Fact from Fiction. Cannabis and Cannabinoid Research. 2021. PubMed abstract read 2026-10-22.
- US Food and Drug Administration. FDA Regulation of Cannabis and Cannabis-Derived Products, Including Cannabidiol (CBD): Questions and Answers. Read 2026-10-22.
- Congressional Research Service. Changes to the Statutory Definition of Hemp and Implications for Agricultural Policy (CRS In Focus IF13136), updated September 28, 2026. Read 2026-10-22.